Jump to section

References

Trials

Economics

Properties

Spectra

Taxonomy

Levothyroxine

Targets (2)Enzymes (2)Carriers (3)Transporters (9)Biointeractions (7)

Identification

Name

Levothyroxine

Accession Number

DB00451 (APRD00235, EXPT02993)

Type

Small Molecule

Groups

Approved

Description

The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (monoiodotyrosine) and the coupling of iodotyrosines (diiodotyrosine) in the thyroglobulin. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form triiodothyronine which exerts a broad spectrum of stimulatory effects on cell metabolism.

Structure

Similar Structures

Synonyms

3,3',5,5'-Tetraiodo-L-thyronine
3,5,3',5'-TETRAIODO-L-thyronine
4-(4-Hydroxy-3,5-diiodophenoxy)-3,5-diiodo-L-phenylalanine
L-T4
L-Thyroxine
Levothyroxin
LT4
O-(4-Hydroxy-3,5-diidophenyl)-3,5-diiodo-L-tyrosine
O-(4-Hydroxy-3,5-diiodophenyl)-3,5-diiodo-L-tyrosine
T4

Product Ingredients

Ingredient	UNII	CAS	InChI Key
Levothyroxine sodium	054I36CPMN	55-03-8	YDTFRJLNMPSCFM-YDALLXLXSA-M

Product Images

Prescription Products

Name	Dosage	Strength	Route	Labeller	Marketing Start	Marketing End
Eltroxin	Tablet	100 mcg	Oral	Aspen Pharmacare Canada Inc.	1998-11-27	Not applicable
Eltroxin	Tablet	300 mcg	Oral	Aspen Pharmacare Canada Inc.	1998-02-11	Not applicable
Eltroxin	Tablet	150 mcg	Oral	Aspen Pharmacare Canada Inc.	1974-12-31	Not applicable
Eltroxin	Tablet	50 mcg	Oral	Aspen Pharmacare Canada Inc.	1951-12-30	Not applicable
Eltroxin	Tablet	200 mcg	Oral	Aspen Pharmacare Canada Inc.	1997-04-02	Not applicable
Eltroxin 150 Tab	Tablet	150 mcg	Oral	Glaxo Canada Inc	1974-12-31	1999-08-12
Eltroxin Tab 100mcg	Tablet	.1 mg	Oral	Glaxo Canada Inc	1951-12-31	1999-08-12
Eltroxin Tab 200mcg	Tablet	.2 mg	Oral	Glaxo Canada Inc	1960-12-31	1998-07-30
Eltroxin Tab 300mcg	Tablet	.3 mg	Oral	Glaxo Canada Inc	1966-12-31	1998-07-30
Eltroxin Tab 50mcg	Tablet	.05 mg	Oral	Glaxo Canada Inc	1951-12-31	1998-07-30

Generic Prescription Products

Name	Dosage	Strength	Route	Labeller	Marketing Start	Marketing End
Levothyroxine Sodium	Tablet	150 ug/1	Oral	Pd Rx Pharmaceuticals, Inc.	2002-11-01	Not applicable
Levothyroxine Sodium	Tablet	75 ug/1	Oral	State of Florida DOH Central Pharmacy	2013-01-01	Not applicable
Levothyroxine Sodium	Tablet	.112 mg/1	Oral	Remedy Repack	2010-08-04	2016-10-21
Levothyroxine Sodium	Tablet	112 ug/1	Oral	Physicians Total Care, Inc.	2010-01-14	Not applicable
Levothyroxine Sodium	Tablet	300 ug/1	Oral	Mylan Pharmaceuticals	2002-11-01	Not applicable
Levothyroxine Sodium	Tablet	88 ug/1	Oral	Remedy Repack	2013-07-05	2016-10-13
Levothyroxine Sodium	Tablet	50 ug/1	Oral	A S Medication Solutions	2007-02-05	2017-06-20
Levothyroxine Sodium	Tablet	50 ug/1	Oral	Pd Rx Pharmaceuticals, Inc.	2002-11-01	Not applicable
Levothyroxine Sodium	Tablet	25 ug/1	Oral	Physicians Total Care, Inc.	2005-04-04	Not applicable
Levothyroxine Sodium	Tablet	.112 mg/1	Oral	Remedy Repack	2011-06-22	2016-10-13

International/Other Brands

Eutirox (Merck) / Letrox (Berlin-Chemie) / Levaxin (Nycomed) / Levothyrox (Merck) / Novothyrox / Oroxine (GlaxoSmithKline) / Thyrax (Merck)

Mixture Products

Name	Ingredients	Dosage	Route	Labeller	Marketing Start	Marketing End
Levothyroxine and Liothyronine Thyroid	Levothyroxine (57 ug/1) + Liothyronine (13.5 ug/1)	Tablet	Oral	Westminster	2017-09-19	Not applicable
Levothyroxine and Liothyronine Thyroid	Levothyroxine (19 ug/1) + Liothyronine (4.5 ug/1)	Tablet	Oral	Westminster	2017-09-19	Not applicable
Levothyroxine and Liothyronine Thyroid	Levothyroxine (38 ug/1) + Liothyronine (9 ug/1)	Tablet	Oral	Westminster	2017-09-19	Not applicable
NP Thyroid 120	Levothyroxine (76 ug/1) + Liothyronine (18 ug/1)	Tablet	Oral	Acella Pharmaceuticals, LLC	2010-11-11	Not applicable
NP Thyroid 120	Levothyroxine (76 ug/1) + Liothyronine (18 ug/1)	Tablet	Oral	Preferreed Pharmaceuticals Inc.	2017-10-12	Not applicable
NP Thyroid 15	Levothyroxine (9.5 ug/1) + Liothyronine (2.25 ug/1)	Tablet	Oral	Preferreed Pharmaceuticals Inc.	2017-10-12	Not applicable
NP Thyroid 15	Levothyroxine (9.5 ug/1) + Liothyronine (2.25 ug/1)	Tablet	Oral	Acella Pharmaceuticals, LLC	2010-11-11	Not applicable
NP Thyroid 30	Levothyroxine (19 ug/1) + Liothyronine (4.5 ug/1)	Tablet	Oral	Acella Pharmaceuticals, LLC	2010-11-11	Not applicable
NP Thyroid 30	Levothyroxine (19 ug/1) + Liothyronine (4.5 ug/1)	Tablet	Topical	Preferreed Pharmaceuticals Inc.	2017-10-12	Not applicable
NP Thyroid 30	Levothyroxine (19 ug/1) + Liothyronine (4.5 ug/1)	Tablet	Oral	bryant ranch prepack	2010-11-11	Not applicable

Categories

UNII

Q51BO43MG4

CAS number

51-48-9

Weight

Average: 776.87
Monoisotopic: 776.686681525

Chemical Formula

C₁₅H₁₁I₄NO₄

InChI Key

XUIIKFGFIJCVMT-LBPRGKRZSA-N

InChI

InChI=1S/C15H11I4NO4/c16-8-4-7(5-9(17)13(8)21)24-14-10(18)1-6(2-11(14)19)3-12(20)15(22)23/h1-2,4-5,12,21H,3,20H2,(H,22,23)/t12-/m0/s1

IUPAC Name

(2S)-2-amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propanoic acid

SMILES

N[[email protected]@H](CC1=CC(I)=C(OC2=CC(I)=C(O)C(I)=C2)C(I)=C1)C(O)=O

Pharmacology

Indication

For use alone or in combination with antithyroid agents to treat hypothyroidism, goiter, chronic lymphocytic thyroiditis, myxedema coma, and stupor.

Structured Indications

Pharmacodynamics

Levothyroxine (T₄) is a synthetically prepared levo isomer of thyroxine, the major hormone secreted from the thyroid gland. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form triiodothyronine (T₃) which exerts a broad spectrum of stimulatory effects on cell metabolism. Thyroid hormone increases the metabolic rate of cells of all tissues in the body. In the fetus and newborn, thyroid hormone is important for the growth and development of all tissues including bones and the brain. In adults, thyroid hormone helps to maintain brain function, food metabolism, and body temperature, among other effects. The symptoms of thyroid deficiency relieved by levothyroxine include slow speech, lack of energy, weight gain, hair loss, dry thick skin and unusual sensitivity to cold.

Mechanism of action

Levothyroxine acts like the endogenous thyroid hormone thyroxine (T₄, a tetra-iodinated tyrosine derivative). In the liver and kidney, T₄ is converted to T₃, the active metabolite. In order to increase solubility, the thyroid hormones attach to thyroid hormone binding proteins, thyroxin-binding globulin, and thyroxin-binding prealbumin (transthyretin). Transport and binding to thyroid hormone receptors in the cytoplasm and nucleus then takes place. Thus by acting as a replacement for natural thyroxine, symptoms of thyroxine deficiency are relieved.

Target	Actions	Organism
AThyroid hormone receptor alpha	agonist	Human
AThyroid hormone receptor beta	agonist	Human

Absorption

Bioavailability varies from 48% to 80%. Human studies have confirmed the importance of an intact jejunum and ileum for levothyroxine absorption and have shown some absorption from the duodenum.

Volume of distribution

Not Available

Protein binding

> 99% to serum proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA), and albumin (TBA)

Metabolism

Approximately 70% of secreted T₄ is deiodinated to equal amounts of T₃ and reverse triiodothyronine (rT₃), which is calorigenically inactive. Elimination of T₄ and T₃ involves hepatic conjugation to glucuronic and sulfuric acids. The hormones undergo enterohepatic circulation as conjugates are hydrolyzed in the intestine and reabsorbed. Conjugated compounds that reach the colon are hydrolyzed and eliminated as free compounds in the feces. Other minor T₄ metabolites have been identified.

Route of elimination

Thyroid hormones are primarily eliminated by the kidneys.

Half life

T₄, 6 to 7 days. T₃, 1 to 2 days.

Clearance

Not Available

Toxicity

LD₅₀=20 mg/kg (orally in rat). Hypermetabolic state indistinguishable from thyrotoxicosis of endogenous origin. Symptoms of thyrotoxicosis include weight loss, increased appetite, palpitations, nervousness, diarrhea, abdominal cramps, sweating, tachycardia, increased pulse and blood pressure, cardiac arrhythmias, tremors, insomnia, heat intolerance, fever, and menstrual irregularities.

Affected organisms

Humans and other mammals

Pathways

Pathway	Category
Thyroid hormone synthesis	Metabolic

Pharmacogenomic Effects/ADRs

Not Available

Interactions

Drug Interactions

Drug	Interaction	Drug group
Acebutolol	The serum concentration of Acebutolol can be decreased when it is combined with Levothyroxine.	Approved
Acenocoumarol	Levothyroxine may increase the anticoagulant activities of Acenocoumarol.	Approved
Acetaminophen	The serum concentration of Acetaminophen can be decreased when it is combined with Levothyroxine.	Approved
Acetylsalicylic acid	The serum concentration of Acetylsalicylic acid can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Afatinib	The serum concentration of Afatinib can be decreased when it is combined with Levothyroxine.	Approved
Alaproclate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Alaproclate.	Experimental
Aldosterone	The serum concentration of Aldosterone can be decreased when it is combined with Levothyroxine.	Experimental
Alitretinoin	The serum concentration of Alitretinoin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Aluminum hydroxide	The serum concentration of Levothyroxine can be decreased when it is combined with Aluminum hydroxide.	Approved
Ambrisentan	The serum concentration of Ambrisentan can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Ambroxol acefyllinate	The metabolism of Ambroxol acefyllinate can be increased when combined with Levothyroxine.	Experimental
Amineptine	Levothyroxine may increase the arrhythmogenic activities of Amineptine.	Illicit, Withdrawn
Aminophylline	The metabolism of Aminophylline can be increased when combined with Levothyroxine.	Approved
Amiodarone	The metabolism of Levothyroxine can be decreased when combined with Amiodarone.	Approved, Investigational
Amitriptyline	The serum concentration of Amitriptyline can be decreased when it is combined with Levothyroxine.	Approved
Amodiaquine	The serum concentration of Amodiaquine can be increased when it is combined with Levothyroxine.	Approved
Apixaban	The serum concentration of Apixaban can be decreased when it is combined with Levothyroxine.	Approved
Aprepitant	The serum concentration of Levothyroxine can be increased when it is combined with Aprepitant.	Approved, Investigational
Arsenic trioxide	The serum concentration of Arsenic trioxide can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Atazanavir	The metabolism of Levothyroxine can be decreased when combined with Atazanavir.	Approved, Investigational
Atenolol	The serum concentration of Atenolol can be decreased when it is combined with Levothyroxine.	Approved
Atomoxetine	The metabolism of Levothyroxine can be decreased when combined with Atomoxetine.	Approved
Axitinib	The serum concentration of Axitinib can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Belinostat	The serum concentration of Belinostat can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Betamethasone	The serum concentration of Betamethasone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Boceprevir	The metabolism of Levothyroxine can be decreased when combined with Boceprevir.	Withdrawn
Bortezomib	The metabolism of Levothyroxine can be decreased when combined with Bortezomib.	Approved, Investigational
Bosentan	The serum concentration of Levothyroxine can be decreased when it is combined with Bosentan.	Approved, Investigational
Bosutinib	The serum concentration of Bosutinib can be decreased when it is combined with Levothyroxine.	Approved
Brentuximab vedotin	The serum concentration of Brentuximab vedotin can be decreased when it is combined with Levothyroxine.	Approved
Bromocriptine	The serum concentration of Bromocriptine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Cabazitaxel	The serum concentration of Cabazitaxel can be decreased when it is combined with Levothyroxine.	Approved
Caffeine	The serum concentration of Caffeine can be decreased when it is combined with Levothyroxine.	Approved
Calcium	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium.	Nutraceutical
Calcium Acetate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium Acetate.	Approved
Calcium Carbonate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium Carbonate.	Approved
Calcium Citrate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium Citrate.	Approved
Calcium glubionate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium glubionate.	Approved
Calcium Gluceptate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium Gluceptate.	Approved
Calcium gluconate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium gluconate.	Approved, Vet Approved
Calcium lactate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium lactate.	Approved, Experimental, Vet Approved
Calcium lactate gluconate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium lactate gluconate.	Experimental
Calcium laevulate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium laevulate.	Experimental
Calcium pangamate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium pangamate.	Experimental
Calcium Phosphate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Calcium Phosphate.	Approved
Camptothecin	The serum concentration of Camptothecin can be decreased when it is combined with Levothyroxine.	Experimental
Canagliflozin	The serum concentration of Canagliflozin can be decreased when it is combined with Levothyroxine.	Approved
Carbamazepine	The serum concentration of Levothyroxine can be decreased when it is combined with Carbamazepine.	Approved, Investigational
Carfilzomib	The serum concentration of Carfilzomib can be decreased when it is combined with Levothyroxine.	Approved
Casein	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Casein.	Approved
Ceritinib	The serum concentration of Levothyroxine can be increased when it is combined with Ceritinib.	Approved
Cerivastatin	The serum concentration of Cerivastatin can be decreased when it is combined with Levothyroxine.	Withdrawn
Chlorotrianisene	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Chlorotrianisene.	Withdrawn
Chlorpromazine	The serum concentration of Chlorpromazine can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Cholestyramine	The serum concentration of Levothyroxine can be decreased when it is combined with Cholestyramine.	Approved
Cimetidine	The serum concentration of Cimetidine can be decreased when it is combined with Levothyroxine.	Approved
Cisplatin	The serum concentration of Cisplatin can be decreased when it is combined with Levothyroxine.	Approved
Citalopram	The serum concentration of Citalopram can be decreased when it is combined with Levothyroxine.	Approved
Clarithromycin	The metabolism of Levothyroxine can be decreased when combined with Clarithromycin.	Approved
Clemastine	The metabolism of Levothyroxine can be decreased when combined with Clemastine.	Approved
Clobazam	The serum concentration of Clobazam can be decreased when it is combined with Levothyroxine.	Approved, Illicit
Clomifene	The serum concentration of Clomifene can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Clomipramine	Levothyroxine may increase the arrhythmogenic activities of Clomipramine.	Approved, Vet Approved
Clonidine	The serum concentration of Clonidine can be decreased when it is combined with Levothyroxine.	Approved
Clopidogrel	The serum concentration of Clopidogrel can be decreased when it is combined with Levothyroxine.	Approved, Nutraceutical
Clorindione	Levothyroxine may increase the anticoagulant activities of Clorindione.	Experimental
Clotrimazole	The metabolism of Levothyroxine can be decreased when combined with Clotrimazole.	Approved, Vet Approved
Clozapine	The serum concentration of Clozapine can be decreased when it is combined with Levothyroxine.	Approved
Cobicistat	The metabolism of Levothyroxine can be decreased when combined with Cobicistat.	Approved
Cobimetinib	The serum concentration of Cobimetinib can be decreased when it is combined with Levothyroxine.	Approved
Colchicine	The serum concentration of Colchicine can be decreased when it is combined with Levothyroxine.	Approved
Colesevelam	The serum concentration of Levothyroxine can be decreased when it is combined with Colesevelam.	Approved
Colestipol	The serum concentration of Levothyroxine can be decreased when it is combined with Colestipol.	Approved
Conivaptan	The serum concentration of Levothyroxine can be increased when it is combined with Conivaptan.	Approved, Investigational
Conjugated estrogens	The serum concentration of Conjugated estrogens can be decreased when it is combined with Levothyroxine.	Approved
Copanlisib	The serum concentration of Copanlisib can be decreased when it is combined with Levothyroxine.	Approved
Crizotinib	The metabolism of Levothyroxine can be decreased when combined with Crizotinib.	Approved
Cyclobenzaprine	Levothyroxine may increase the arrhythmogenic activities of Cyclobenzaprine.	Approved
Cyclosporine	The metabolism of Levothyroxine can be decreased when combined with Cyclosporine.	Approved, Investigational, Vet Approved
Dabigatran etexilate	The serum concentration of Dabigatran etexilate can be decreased when it is combined with Levothyroxine.	Approved
Dabrafenib	The serum concentration of Levothyroxine can be decreased when it is combined with Dabrafenib.	Approved
Dactinomycin	The serum concentration of Dactinomycin can be decreased when it is combined with Levothyroxine.	Approved
Daidzein	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Daidzein.	Experimental
Dapagliflozin	The serum concentration of Dapagliflozin can be decreased when it is combined with Levothyroxine.	Approved
Dapoxetine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Dapoxetine.	Investigational
Darunavir	The metabolism of Levothyroxine can be decreased when combined with Darunavir.	Approved
Dasatinib	The serum concentration of Levothyroxine can be increased when it is combined with Dasatinib.	Approved, Investigational
Daunorubicin	The serum concentration of Daunorubicin can be decreased when it is combined with Levothyroxine.	Approved
Debrisoquin	The serum concentration of Debrisoquin can be decreased when it is combined with Levothyroxine.	Approved
Deferasirox	The serum concentration of Levothyroxine can be decreased when it is combined with Deferasirox.	Approved, Investigational
Delavirdine	The metabolism of Levothyroxine can be decreased when combined with Delavirdine.	Approved
Desipramine	Levothyroxine may increase the arrhythmogenic activities of Desipramine.	Approved
Desvenlafaxine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Desvenlafaxine.	Approved
Dexamethasone	The serum concentration of Dexamethasone can be decreased when it is combined with Levothyroxine.	Approved, Investigational, Vet Approved
Diazepam	The serum concentration of Diazepam can be decreased when it is combined with Levothyroxine.	Approved, Illicit, Vet Approved
Dibenzepin	Levothyroxine may increase the arrhythmogenic activities of Dibenzepin.	Experimental
Dicoumarol	Levothyroxine may increase the anticoagulant activities of Dicoumarol.	Approved
Dienestrol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Dienestrol.	Approved
Diethylstilbestrol	The serum concentration of Diethylstilbestrol can be decreased when it is combined with Levothyroxine.	Approved
Digitoxin	The serum concentration of Digitoxin can be decreased when it is combined with Levothyroxine.	Approved
Digoxin	The serum concentration of Digoxin can be decreased when it is combined with Levothyroxine.	Approved
Dihydroergotamine	The metabolism of Levothyroxine can be decreased when combined with Dihydroergotamine.	Approved
Dihydrotestosterone	The serum concentration of Dihydrotestosterone can be decreased when it is combined with Levothyroxine.	Illicit
Diltiazem	The metabolism of Levothyroxine can be decreased when combined with Diltiazem.	Approved
Diphenadione	Levothyroxine may increase the anticoagulant activities of Diphenadione.	Experimental
Dipyridamole	The serum concentration of Dipyridamole can be decreased when it is combined with Levothyroxine.	Approved
Docetaxel	The serum concentration of Docetaxel can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Domperidone	The serum concentration of Domperidone can be decreased when it is combined with Levothyroxine.	Approved, Investigational, Vet Approved
Dosulepin	Levothyroxine may increase the arrhythmogenic activities of Dosulepin.	Approved
Doxepin	Levothyroxine may increase the arrhythmogenic activities of Doxepin.	Approved
Doxorubicin	The serum concentration of Doxorubicin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Doxycycline	The metabolism of Levothyroxine can be decreased when combined with Doxycycline.	Approved, Investigational, Vet Approved
Dronedarone	The metabolism of Levothyroxine can be decreased when combined with Dronedarone.	Approved
Duloxetine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Duloxetine.	Approved
Dyphylline	The metabolism of Dyphylline can be increased when combined with Levothyroxine.	Approved
Edoxaban	The serum concentration of Edoxaban can be decreased when it is combined with Levothyroxine.	Approved
Elbasvir	The serum concentration of Elbasvir can be decreased when it is combined with Levothyroxine.	Approved
Eletriptan	The serum concentration of Eletriptan can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Enasidenib	The serum concentration of Enasidenib can be decreased when it is combined with Levothyroxine.	Approved
Enzalutamide	The serum concentration of Levothyroxine can be decreased when it is combined with Enzalutamide.	Approved
Epimestrol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Epimestrol.	Experimental
Epinastine	The serum concentration of Epinastine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Equol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Equol.	Investigational
Erlotinib	The serum concentration of Erlotinib can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Erythromycin	The metabolism of Levothyroxine can be decreased when combined with Erythromycin.	Approved, Vet Approved
Escitalopram	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Escitalopram.	Approved, Investigational
Esmirtazapine	Levothyroxine may increase the arrhythmogenic activities of Esmirtazapine.	Investigational
Estradiol	The serum concentration of Estradiol can be decreased when it is combined with Levothyroxine.	Approved, Investigational, Vet Approved
Estriol	The serum concentration of Estriol can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Estrone	The serum concentration of Estrone can be decreased when it is combined with Levothyroxine.	Approved
Ethinyl Estradiol	The serum concentration of Ethinyl Estradiol can be decreased when it is combined with Levothyroxine.	Approved
Ethyl biscoumacetate	Levothyroxine may increase the anticoagulant activities of Ethyl biscoumacetate.	Withdrawn
Etoperidone	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Etoperidone.	Approved
Etoposide	The serum concentration of Etoposide can be decreased when it is combined with Levothyroxine.	Approved
Ezetimibe	The serum concentration of Ezetimibe can be decreased when it is combined with Levothyroxine.	Approved
Ferric Carboxymaltose	The serum concentration of Levothyroxine can be decreased when it is combined with Ferric Carboxymaltose.	Approved
Ferric Citrate	The serum concentration of Levothyroxine can be decreased when it is combined with Ferric Citrate.	Approved
Ferric pyrophosphate	The serum concentration of Levothyroxine can be decreased when it is combined with Ferric pyrophosphate.	Approved
Fesoterodine	The serum concentration of Fesoterodine can be decreased when it is combined with Levothyroxine.	Approved
Fexofenadine	The serum concentration of Fexofenadine can be decreased when it is combined with Levothyroxine.	Approved
Fidaxomicin	The serum concentration of Fidaxomicin can be decreased when it is combined with Levothyroxine.	Approved
Fluconazole	The metabolism of Levothyroxine can be decreased when combined with Fluconazole.	Approved
Fluindione	Levothyroxine may increase the anticoagulant activities of Fluindione.	Investigational
Fluoxetine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Fluoxetine.	Approved, Vet Approved
Fluticasone furoate	The serum concentration of Fluticasone furoate can be decreased when it is combined with Levothyroxine.	Approved
Fluvoxamine	The metabolism of Levothyroxine can be decreased when combined with Fluvoxamine.	Approved, Investigational
Fosamprenavir	The metabolism of Levothyroxine can be decreased when combined with Fosamprenavir.	Approved
Fosaprepitant	The serum concentration of Levothyroxine can be increased when it is combined with Fosaprepitant.	Approved
Fosphenytoin	The serum concentration of Levothyroxine can be decreased when it is combined with Fosphenytoin.	Approved
Fusidic Acid	The serum concentration of Levothyroxine can be increased when it is combined with Fusidic Acid.	Approved
Gefitinib	The serum concentration of Gefitinib can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Gemcitabine	The serum concentration of Gemcitabine can be decreased when it is combined with Levothyroxine.	Approved
Genistein	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Genistein.	Investigational
Glecaprevir	The serum concentration of Glecaprevir can be decreased when it is combined with Levothyroxine.	Approved
Grazoprevir	The serum concentration of Grazoprevir can be decreased when it is combined with Levothyroxine.	Approved
Grepafloxacin	The serum concentration of Grepafloxacin can be decreased when it is combined with Levothyroxine.	Withdrawn
Haloperidol	The serum concentration of Haloperidol can be decreased when it is combined with Levothyroxine.	Approved
Hexestrol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Hexestrol.	Withdrawn
Hydrocortisone	The serum concentration of Hydrocortisone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Ibuprofen	The serum concentration of Ibuprofen can be decreased when it is combined with Levothyroxine.	Approved
Idelalisib	The serum concentration of Levothyroxine can be increased when it is combined with Idelalisib.	Approved
Imatinib	The metabolism of Levothyroxine can be decreased when combined with Imatinib.	Approved
Imipramine	The serum concentration of Imipramine can be decreased when it is combined with Levothyroxine.	Approved
Indacaterol	The serum concentration of Indacaterol can be decreased when it is combined with Levothyroxine.	Approved
Indalpine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Indalpine.	Investigational, Withdrawn
Indinavir	The metabolism of Levothyroxine can be decreased when combined with Indinavir.	Approved
Indomethacin	The serum concentration of Indomethacin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Inotuzumab ozogamicin	The serum concentration of Inotuzumab ozogamicin can be decreased when it is combined with Levothyroxine.	Approved
Iodide I-131	The therapeutic efficacy of Iodide I-131 can be decreased when used in combination with Levothyroxine.	Approved
Iprindole	Levothyroxine may increase the arrhythmogenic activities of Iprindole.	Experimental
Irinotecan	The serum concentration of Irinotecan can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Iron	The serum concentration of Levothyroxine can be decreased when it is combined with Iron.	Approved
Iron Dextran	The serum concentration of Levothyroxine can be decreased when it is combined with Iron Dextran.	Approved, Vet Approved
Iron saccharate	The serum concentration of Levothyroxine can be decreased when it is combined with Iron saccharate.	Approved
Isavuconazonium	The metabolism of Levothyroxine can be decreased when combined with Isavuconazonium.	Approved, Investigational
Isradipine	The metabolism of Levothyroxine can be decreased when combined with Isradipine.	Approved
Itraconazole	The metabolism of Levothyroxine can be decreased when combined with Itraconazole.	Approved, Investigational
Ivacaftor	The serum concentration of Levothyroxine can be increased when it is combined with Ivacaftor.	Approved
Ivermectin	The serum concentration of Ivermectin can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Ketazolam	The serum concentration of Ketazolam can be decreased when it is combined with Levothyroxine.	Approved
Ketoconazole	The metabolism of Levothyroxine can be decreased when combined with Ketoconazole.	Approved, Investigational
Lamivudine	The serum concentration of Lamivudine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Lamotrigine	The serum concentration of Lamotrigine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Lansoprazole	The serum concentration of Lansoprazole can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Lanthanum carbonate	The serum concentration of Levothyroxine can be decreased when it is combined with Lanthanum carbonate.	Approved
Ledipasvir	The serum concentration of Ledipasvir can be decreased when it is combined with Levothyroxine.	Approved
Lenalidomide	The serum concentration of Lenalidomide can be decreased when it is combined with Levothyroxine.	Approved
Lenvatinib	The serum concentration of Lenvatinib can be decreased when it is combined with Levothyroxine.	Approved
Levetiracetam	The serum concentration of Levetiracetam can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Levofloxacin	The serum concentration of Levofloxacin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Levomilnacipran	The serum concentration of Levomilnacipran can be decreased when it is combined with Levothyroxine.	Approved
Linagliptin	The serum concentration of Linagliptin can be decreased when it is combined with Levothyroxine.	Approved
Lofepramine	Levothyroxine may increase the arrhythmogenic activities of Lofepramine.	Experimental
Loperamide	The serum concentration of Loperamide can be decreased when it is combined with Levothyroxine.	Approved
Lopinavir	The metabolism of Levothyroxine can be decreased when combined with Lopinavir.	Approved
Losartan	The serum concentration of Losartan can be decreased when it is combined with Levothyroxine.	Approved
Lovastatin	The metabolism of Levothyroxine can be decreased when combined with Lovastatin.	Approved, Investigational
Luliconazole	The serum concentration of Levothyroxine can be increased when it is combined with Luliconazole.	Approved
Lumacaftor	The metabolism of Levothyroxine can be increased when combined with Lumacaftor.	Approved
Magnesium Hydroxide	The serum concentration of Levothyroxine can be decreased when it is combined with Magnesium Hydroxide.	Approved
Magnesium oxide	The serum concentration of Levothyroxine can be decreased when it is combined with Magnesium oxide.	Approved
Magnesium salicylate	The serum concentration of Levothyroxine can be decreased when it is combined with Magnesium salicylate.	Approved
Magnesium Sulfate	The serum concentration of Levothyroxine can be decreased when it is combined with Magnesium Sulfate.	Approved, Vet Approved
Mannitol	The serum concentration of Mannitol can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Mestranol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Mestranol.	Approved
Methallenestril	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Methallenestril.	Experimental
Methotrexate	The serum concentration of Methotrexate can be decreased when it is combined with Levothyroxine.	Approved
Methylprednisolone	The serum concentration of Methylprednisolone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Metoprolol	The serum concentration of Metoprolol can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Midazolam	The serum concentration of Midazolam can be decreased when it is combined with Levothyroxine.	Approved, Illicit
Mifepristone	The serum concentration of Levothyroxine can be increased when it is combined with Mifepristone.	Approved, Investigational
Milnacipran	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Milnacipran.	Approved
Mirabegron	The serum concentration of Mirabegron can be decreased when it is combined with Levothyroxine.	Approved
Mirtazapine	Levothyroxine may increase the arrhythmogenic activities of Mirtazapine.	Approved
Mitotane	The serum concentration of Levothyroxine can be decreased when it is combined with Mitotane.	Approved
Mitoxantrone	The serum concentration of Mitoxantrone can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Morphine	The serum concentration of Morphine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Moxestrol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Moxestrol.	Experimental
Mycophenolate mofetil	The serum concentration of Mycophenolate mofetil can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Nadolol	The serum concentration of Nadolol can be decreased when it is combined with Levothyroxine.	Approved
Naloxone	The serum concentration of Naloxone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Nefazodone	The metabolism of Levothyroxine can be decreased when combined with Nefazodone.	Approved, Withdrawn
Nelfinavir	The metabolism of Levothyroxine can be decreased when combined with Nelfinavir.	Approved
Netupitant	The serum concentration of Levothyroxine can be increased when it is combined with Netupitant.	Approved
Nevirapine	The metabolism of Levothyroxine can be increased when combined with Nevirapine.	Approved
Nicardipine	The serum concentration of Nicardipine can be decreased when it is combined with Levothyroxine.	Approved
Nifedipine	The serum concentration of Nifedipine can be decreased when it is combined with Levothyroxine.	Approved
Nilotinib	The metabolism of Levothyroxine can be decreased when combined with Nilotinib.	Approved, Investigational
Nintedanib	The serum concentration of Nintedanib can be decreased when it is combined with Levothyroxine.	Approved
Nizatidine	The serum concentration of Nizatidine can be decreased when it is combined with Levothyroxine.	Approved
Nortriptyline	Levothyroxine may increase the arrhythmogenic activities of Nortriptyline.	Approved
Odanacatib	The serum concentration of Odanacatib can be decreased when it is combined with Levothyroxine.	Investigational
Olanzapine	The serum concentration of Olanzapine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Olaparib	The metabolism of Levothyroxine can be decreased when combined with Olaparib.	Approved
Ombitasvir	The serum concentration of Ombitasvir can be decreased when it is combined with Levothyroxine.	Approved
Opipramol	Levothyroxine may increase the arrhythmogenic activities of Opipramol.	Investigational
Orlistat	The serum concentration of Levothyroxine can be decreased when it is combined with Orlistat.	Approved, Investigational
Osimertinib	The serum concentration of Levothyroxine can be increased when it is combined with Osimertinib.	Approved
Paclitaxel	The serum concentration of Paclitaxel can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Palbociclib	The serum concentration of Levothyroxine can be increased when it is combined with Palbociclib.	Approved
Panobinostat	The serum concentration of Panobinostat can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Paroxetine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Paroxetine.	Approved, Investigational
Pazopanib	The serum concentration of Pazopanib can be decreased when it is combined with Levothyroxine.	Approved
Pentobarbital	The metabolism of Levothyroxine can be increased when combined with Pentobarbital.	Approved, Vet Approved
Phenindione	Levothyroxine may increase the anticoagulant activities of Phenindione.	Approved
Phenobarbital	The metabolism of Levothyroxine can be increased when combined with Phenobarbital.	Approved
Phenprocoumon	Levothyroxine may increase the anticoagulant activities of Phenprocoumon.	Approved
Phenytoin	The serum concentration of Levothyroxine can be decreased when it is combined with Phenytoin.	Approved, Vet Approved
Pibrentasvir	The serum concentration of Pibrentasvir can be decreased when it is combined with Levothyroxine.	Approved
Piracetam	The risk or severity of adverse effects can be increased when Piracetam is combined with Levothyroxine.	Approved
Pitavastatin	The serum concentration of Pitavastatin can be decreased when it is combined with Levothyroxine.	Approved
Polaprezinc	The serum concentration of Levothyroxine can be decreased when it is combined with Polaprezinc.	Approved
Polyestradiol phosphate	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Polyestradiol phosphate.	Approved
Pomalidomide	The serum concentration of Pomalidomide can be decreased when it is combined with Levothyroxine.	Approved
Ponatinib	The serum concentration of Ponatinib can be decreased when it is combined with Levothyroxine.	Approved
Posaconazole	The metabolism of Levothyroxine can be decreased when combined with Posaconazole.	Approved, Investigational, Vet Approved
Pravastatin	The serum concentration of Pravastatin can be decreased when it is combined with Levothyroxine.	Approved
Prazosin	The serum concentration of Prazosin can be decreased when it is combined with Levothyroxine.	Approved
Prednisolone	The serum concentration of Prednisolone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Prednisone	The serum concentration of Prednisone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Primidone	The metabolism of Levothyroxine can be increased when combined with Primidone.	Approved, Vet Approved
Progesterone	The serum concentration of Progesterone can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Promestriene	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Promestriene.	Investigational
Propranolol	The serum concentration of Propranolol can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Protriptyline	Levothyroxine may increase the arrhythmogenic activities of Protriptyline.	Approved
Quetiapine	The serum concentration of Quetiapine can be decreased when it is combined with Levothyroxine.	Approved
Quinestrol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Quinestrol.	Approved
Quinidine	The serum concentration of Quinidine can be decreased when it is combined with Levothyroxine.	Approved
Quinine	The serum concentration of Quinine can be decreased when it is combined with Levothyroxine.	Approved
Raloxifene	Raloxifene can cause a decrease in the absorption of Levothyroxine resulting in a reduced serum concentration and potentially a decrease in efficacy.	Approved, Investigational
Ranitidine	The serum concentration of Ranitidine can be decreased when it is combined with Levothyroxine.	Approved
Ranolazine	The metabolism of Levothyroxine can be decreased when combined with Ranolazine.	Approved, Investigational
Reserpine	The serum concentration of Reserpine can be decreased when it is combined with Levothyroxine.	Approved
Rifabutin	The metabolism of Levothyroxine can be increased when combined with Rifabutin.	Approved
Rifampicin	The serum concentration of Levothyroxine can be decreased when it is combined with Rifampicin.	Approved
Rifapentine	The metabolism of Levothyroxine can be increased when combined with Rifapentine.	Approved
Risperidone	The serum concentration of Risperidone can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Ritonavir	The metabolism of Levothyroxine can be decreased when combined with Ritonavir.	Approved, Investigational
Rivaroxaban	The serum concentration of Rivaroxaban can be decreased when it is combined with Levothyroxine.	Approved
Romidepsin	The serum concentration of Romidepsin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Salicylic acid	The serum concentration of Salicylic acid can be decreased when it is combined with Levothyroxine.	Approved, Vet Approved
Saquinavir	The metabolism of Levothyroxine can be decreased when combined with Saquinavir.	Approved, Investigational
Secoisolariciresinol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Secoisolariciresinol.	Investigational
Selexipag	The serum concentration of Selexipag can be decreased when it is combined with Levothyroxine.	Approved
Sertraline	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Sertraline.	Approved
Sevelamer	The serum concentration of Levothyroxine can be decreased when it is combined with Sevelamer.	Approved
Sildenafil	The metabolism of Levothyroxine can be decreased when combined with Sildenafil.	Approved, Investigational
Silodosin	The serum concentration of Silodosin can be decreased when it is combined with Levothyroxine.	Approved
Siltuximab	The serum concentration of Levothyroxine can be decreased when it is combined with Siltuximab.	Approved
Simeprevir	The serum concentration of Levothyroxine can be increased when it is combined with Simeprevir.	Approved
Sitagliptin	The serum concentration of Sitagliptin can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Sofosbuvir	The serum concentration of Sofosbuvir can be decreased when it is combined with Levothyroxine.	Approved
Sorafenib	The serum concentration of Sorafenib can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Sparfloxacin	The serum concentration of Sparfloxacin can be decreased when it is combined with Levothyroxine.	Approved
Sphingosine	The serum concentration of Sphingosine can be decreased when it is combined with Levothyroxine.	Experimental
St. John's Wort	The serum concentration of Levothyroxine can be decreased when it is combined with St. John's Wort.	Nutraceutical
Stiripentol	The serum concentration of Levothyroxine can be increased when it is combined with Stiripentol.	Approved
Sucralfate	The serum concentration of Levothyroxine can be decreased when it is combined with Sucralfate.	Approved
Sulfisoxazole	The metabolism of Levothyroxine can be decreased when combined with Sulfisoxazole.	Approved, Vet Approved
Synthetic Conjugated Estrogens, A	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Synthetic Conjugated Estrogens, A.	Approved
Synthetic Conjugated Estrogens, B	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Synthetic Conjugated Estrogens, B.	Approved
Tacrolimus	The serum concentration of Tacrolimus can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Tamoxifen	The serum concentration of Tamoxifen can be decreased when it is combined with Levothyroxine.	Approved
Taurocholic Acid	The serum concentration of Taurocholic Acid can be decreased when it is combined with Levothyroxine.	Experimental
Technetium Tc-99m sestamibi	The serum concentration of Technetium Tc-99m sestamibi can be decreased when it is combined with Levothyroxine.	Approved
Telaprevir	The metabolism of Levothyroxine can be decreased when combined with Telaprevir.	Withdrawn
Telithromycin	The metabolism of Levothyroxine can be decreased when combined with Telithromycin.	Approved
Temsirolimus	The serum concentration of Temsirolimus can be decreased when it is combined with Levothyroxine.	Approved
Theophylline	The metabolism of Theophylline can be increased when combined with Levothyroxine.	Approved
Tianeptine	Levothyroxine may increase the arrhythmogenic activities of Tianeptine.	Approved
Tibolone	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Tibolone.	Approved
Ticagrelor	The serum concentration of Ticagrelor can be decreased when it is combined with Levothyroxine.	Approved
Ticlopidine	The metabolism of Levothyroxine can be decreased when combined with Ticlopidine.	Approved
Timolol	The serum concentration of Timolol can be decreased when it is combined with Levothyroxine.	Approved
Tioclomarol	Levothyroxine may increase the anticoagulant activities of Tioclomarol.	Experimental
Tocilizumab	The serum concentration of Levothyroxine can be decreased when it is combined with Tocilizumab.	Approved
Tolevamer	The serum concentration of Levothyroxine can be decreased when it is combined with Tolevamer.	Approved
Tolvaptan	The serum concentration of Tolvaptan can be decreased when it is combined with Levothyroxine.	Approved
Topotecan	The serum concentration of Topotecan can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Toremifene	The serum concentration of Toremifene can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Trastuzumab emtansine	The serum concentration of Trastuzumab emtansine can be decreased when it is combined with Levothyroxine.	Approved
Trimipramine	Levothyroxine may increase the arrhythmogenic activities of Trimipramine.	Approved
Ulipristal	The serum concentration of Ulipristal can be decreased when it is combined with Levothyroxine.	Approved
Umeclidinium	The serum concentration of Umeclidinium can be decreased when it is combined with Levothyroxine.	Approved
Vecuronium	The serum concentration of Vecuronium can be decreased when it is combined with Levothyroxine.	Approved
Velpatasvir	The serum concentration of Velpatasvir can be decreased when it is combined with Levothyroxine.	Approved
Venetoclax	The serum concentration of Venetoclax can be decreased when it is combined with Levothyroxine.	Approved
Venlafaxine	The metabolism of Levothyroxine can be decreased when combined with Venlafaxine.	Approved
Verapamil	The metabolism of Levothyroxine can be decreased when combined with Verapamil.	Approved
Vinblastine	The serum concentration of Vinblastine can be decreased when it is combined with Levothyroxine.	Approved
Vincristine	The serum concentration of Vincristine can be decreased when it is combined with Levothyroxine.	Approved, Investigational
Vismodegib	The serum concentration of Vismodegib can be decreased when it is combined with Levothyroxine.	Approved
Voriconazole	The metabolism of Levothyroxine can be decreased when combined with Voriconazole.	Approved, Investigational
Voxilaprevir	The serum concentration of Voxilaprevir can be decreased when it is combined with Levothyroxine.	Approved
Warfarin	Levothyroxine may increase the anticoagulant activities of Warfarin.	Approved
Zeranol	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Zeranol.	Vet Approved
Zidovudine	The serum concentration of Zidovudine can be decreased when it is combined with Levothyroxine.	Approved
Zimelidine	The therapeutic efficacy of Levothyroxine can be decreased when used in combination with Zimelidine.	Withdrawn
Ziprasidone	The metabolism of Levothyroxine can be decreased when combined with Ziprasidone.	Approved

Food Interactions

Absorption increased in fasting state and decreased in malabsorption states.
Consistent administration in relation to meals is recommended.
No iron or calium carbonate within 4 hours of taking this medication.
Oral administration with infant soybean formula, soybean flour, cotton seed meal, walnuts, foods containing large amounts of fiber, ferrous sulfate, and antacids may decrease drug absorption.
Take 30-60 minutes before breakfast.

References

Synthesis Reference

Jivn-Ren Chen, Dimitri C. Papadimitriou, "Stable dosage of levothyroxine sodium and process of production." U.S. Patent US5225204, issued November, 1991.

US5225204

General References

Uchino H, Kanai Y, Kim DK, Wempe MF, Chairoungdua A, Morimoto E, Anders MW, Endou H: Transport of amino acid-related compounds mediated by L-type amino acid transporter 1 (LAT1): insights into the mechanisms of substrate recognition. Mol Pharmacol. 2002 Apr;61(4):729-37. [PubMed:11901210]

External Links

Human Metabolome Database: HMDB00248
KEGG Drug: D08125
KEGG Compound: C01829
PubChem Compound: 5819
PubChem Substance: 46507672
ChemSpider: 5614
BindingDB: 50301375
ChEBI: 18332
ChEMBL: CHEMBL1624
Therapeutic Targets Database: DAP000083
PharmGKB: PA450221
IUPHAR: 2635
Guide to Pharmacology: GtP Drug Page
HET: T44
RxList: RxList Drug Page
Drugs.com: Drugs.com Drug Page
PDRhealth: PDRhealth Drug Page
Wikipedia: Levothyroxine

ATC Codes

H03AA01 — Levothyroxine sodium

AHFS Codes

68:36.04 — Thyroid Agents

PDB Entries

1eta / 1etb / 1f86 / 1hk1 / 1hk2 / 1hk3 / 1hk4 / 1hk5 / 1ict / 1ie4 …

show 12 more

FDA label

Download (54.3 KB)

MSDS

Download (51.7 KB)

Clinical Trials

Clinical Trials

Phase	Status	Purpose	Conditions	Count
0	Enrolling by Invitation	Prevention	Recurrent Pregnancy Losses	1
1	Completed	Not Available	Drug Interactions	1
1	Completed	Not Available	Healthy Volunteers	4
1	Completed	Basic Science	Pharmacokinetics	2
1	Completed	Treatment	Diabetes / Healthy Volunteers	1
1	Completed	Treatment	Healthy Males	1
1, 2	Completed	Treatment	Brain Death	1
1, 2	Not Yet Recruiting	Other	Healthy Volunteers	1
2	Completed	Not Available	Thyroid Diseases	1
2	Terminated	Treatment	Non-Alcoholic Fatty Liver Disease (NAFLD) / Type 2 Diabetes Mellitus	1
2, 3	Active Not Recruiting	Prevention	Graves' Disease	1
2, 3	Completed	Treatment	Bipolar Disorder (BD)	1
2, 3	Completed	Treatment	Subclinical Hypothyroidism	2
2, 3	Not Yet Recruiting	Treatment	Hypothyroidism / Neoplasms / Postoperative Complications	1
2, 3	Recruiting	Treatment	Hypothyroidism	1
3	Active Not Recruiting	Treatment	Hypothyroxinemia	1
3	Completed	Treatment	Congenital Hypothyroidism / Hypothyroidism	1
3	Completed	Treatment	Hypothyroxinemia / Pregnancy / Subclinical Hypothyroidism	1
3	Not Yet Recruiting	Treatment	Transient Hypothyroxinemia of Prematurity (THOP)	1
3	Unknown Status	Treatment	Dyslipidemias	1
4	Active Not Recruiting	Treatment	Endocrine System Diseases / Hypothyroidism / Thyroid Diseases	2
4	Active Not Recruiting	Treatment	Mental Fatigue / Thyroid Dysfunction / Tiredness	1
4	Completed	Not Available	Hypothyroidism	1
4	Completed	Prevention	Graves´ Disease	1
4	Completed	Treatment	Atherosclerosis / Heart Failure, Unspecified / Thyroid Dysfunction	2
4	Completed	Treatment	Bone destruction / Bone Mineral Density / Fractures, Bone / Thyroid Dysfunction	1
4	Completed	Treatment	Euthyroid Sick Syndromes	1
4	Completed	Treatment	Graves' Disease / Toxic Nodular Goitre	1
4	Completed	Treatment	Hypothyroidism	1
4	Completed	Treatment	Subclinical Hypothyroidism	1
4	Not Yet Recruiting	Treatment	Goitre	1
4	Not Yet Recruiting	Treatment	Hypothyroidism;Postablative	1
4	Recruiting	Not Available	Hypothyroidism	1
4	Recruiting	Prevention	Hypothyroidism	1
4	Recruiting	Treatment	Depressive State / Subclinical Hypothyroidism	1
4	Recruiting	Treatment	Heart Failure, Unspecified / Subclinical Hyperthyroidism	1
4	Recruiting	Treatment	Hypothyroidism	1
4	Recruiting	Treatment	Hypothyroidism / Myocardial Infarction (MI)	1
4	Recruiting	Treatment	Postsurgical Hypothyroidism / Thyroid Cancers	1
4	Unknown Status	Basic Science	Diabetes / Hypothyroidism	1
4	Unknown Status	Supportive Care	Brain Dead Organ Donors	1
4	Unknown Status	Treatment	Heart Failure With Reduced Ejection Fraction (HFrEF) / Sub-clinical Hypothyroidism	1
4	Withdrawn	Prevention	Systemic Lupus Erythematosus (SLE)	1
4	Withdrawn	Treatment	Subclinical hypothyroïdism	1
Not Available	Active Not Recruiting	Not Available	Head and Neck Carcinoma / Hypothyroidism; Surgery / Laryngeal Cancer / Laryngeal fistula / Wound Heal	1
Not Available	Completed	Not Available	Recurrent Goiter	1
Not Available	Completed	Not Available	Subclinical Hypothyroidism	1
Not Available	Completed	Basic Science	Hypothyroidism	1
Not Available	Completed	Basic Science	Obesity, Morbid	1
Not Available	Completed	Treatment	Congenital Hypothyroidism	1
Not Available	Completed	Treatment	Diabetes Mellitus (DM)	1
Not Available	Completed	Treatment	Hypothyroidism	1
Not Available	Completed	Treatment	Hypothyroidism / Pregnancy	1
Not Available	Completed	Treatment	Pregnancy / Thyroid Diseases	1
Not Available	Completed	Treatment	Thyroid Nodules	1
Not Available	Recruiting	Not Available	Hypothyroidism	2
Not Available	Recruiting	Not Available	Hypothyroidism / Postsurgical Hypothyroidism	1
Not Available	Recruiting	Other	Subclinical Hypothyroidism	1
Not Available	Recruiting	Treatment	Depressive State / Distress / Feeling Anxious / Thyroid Cancers / Tiredness	1
Not Available	Recruiting	Treatment	Down Syndrome (DS) / Subclinical Hypothyroidism	1
Not Available	Recruiting	Treatment	Hypothyroidism	1
Not Available	Recruiting	Treatment	Pregnancy Related / Thyroid	1
Not Available	Terminated	Basic Science	Hypothyroidism	1
Not Available	Terminated	Treatment	Hypothyroidism / Neoplasms, Brain	1
Not Available	Unknown Status	Diagnostic	Central Hypothyroidism	1
Not Available	Unknown Status	Treatment	Primary Hypothyroidism	1

Pharmacoeconomics

Manufacturers

Institute biochimique sa (ibsa)
Institut biochimique sa ibsa
Vintage pharmaceuticals llc
Alara pharmaceutical corporation
Lloyd inc
Merck kgaa
Mylan pharmaceuticals inc
King pharmaceuticals inc
Abbott laboratories
Jerome stevens pharmaceuticals inc

Packagers

Abbott Laboratories Ltd.
Advanced Pharmaceutical Services Inc.
Akrimax Pharmaceuticals
Amerisource Health Services Corp.
Apotheca Inc.
APP Pharmaceuticals
A-S Medication Solutions LLC
Atlantic Biologicals Corporation
BASF Corp.
Bedford Labs
Ben Venue Laboratories Inc.
Bryant Ranch Prepack
Cardinal Health
Caremark LLC
Comprehensive Consultant Services Inc.
Corepharma LLC
Direct Dispensing Inc.
Direct Pharmaceuticals Inc.
Dispensing Solutions
Diversified Healthcare Services Inc.
Forest Pharmaceuticals
Genpharm LP
Giant Food Inc.
H.E. Butt Grocery Co.
H.J. Harkins Co. Inc.
Heartland Repack Services LLC
Innovative Manufacturing and Distribution Services Inc.
Jerome Stevens Pharmaceuticals Inc.
JMI Daniels Pharmaceuticals Inc.
Kaiser Foundation Hospital
King Pharmaceuticals Inc.
Lake Erie Medical and Surgical Supply
Lannett Co. Inc.
Liberty Pharmaceuticals
Lloyd Pharmaceuticals
Macnary Ltd.
Major Pharmaceuticals
Mckesson Corp.
Medisca Inc.
Merck KGaA
Monarch Pharmacy
Murfreesboro Pharmaceutical Nursing Supply
Mylan
Neuman Distributors Inc.
Nucare Pharmaceuticals Inc.
Palmetto Pharmaceuticals Inc.
Patheon Inc.
PCA LLC
PD-Rx Pharmaceuticals Inc.
Pharmaceutical Utilization Management Program VA Inc.
Pharmacy Service Center
Pharmedix
Physicians Total Care Inc.
Preferred Pharmaceuticals Inc.
Prepackage Specialists
Prepak Systems Inc.
Prescript Pharmaceuticals
Qualitest
Rebel Distributors Corp.
Remedy Repack
Resource Optimization and Innovation LLC
Rite Aid Corp.
Sandhills Packaging Inc.
Sandoz
Simildiet SL
Southwood Pharmaceuticals
Stat Scripts LLC
Teva Pharmaceutical Industries Ltd.
UDL Laboratories
Va Cmop Dallas
Watson Pharmaceuticals

Dosage forms

Form	Route	Strength
Tablet	Oral	.1 mg
Tablet	Oral	.2 mg
Tablet	Oral	.3 mg
Tablet	Oral	.05 mg
Injection, powder, lyophilized, for solution	Intravenous	100 ug/5mL
Injection, powder, lyophilized, for solution	Intravenous	200 ug/5mL
Injection, powder, lyophilized, for solution	Intravenous	500 ug/5mL
Tablet	Oral	.025 mg/1
Tablet	Oral	.05 mg/1
Tablet	Oral	.075 mg/1
Tablet	Oral	.088 mg/1
Tablet	Oral	.1 mg/1
Tablet	Oral	.112 mg/1
Tablet	Oral	.125 mg/1
Tablet	Oral	.137 mg/1
Tablet	Oral	.15 mg/1
Tablet	Oral	.175 mg/1
Tablet	Oral	.2 mg/1
Tablet	Oral	.3 mg/1
Tablet	Oral	112 ug/1
Tablet	Oral	125 ug/1
Tablet	Oral	175 ug/1
Tablet	Oral	25 ug/1
Tablet	Oral	50 ug/1
Tablet	Oral	75 ug/1
Powder, for solution	Intramuscular; Intravenous	200 mcg
Powder, for solution	Intramuscular; Intravenous	500 mcg
Tablet	Oral
Tablet	Topical
Tablet	Oral	100 ug/1
Tablet	Oral	137 mcg
Tablet	Oral	137 ug/1
Tablet	Oral	150 ug/1
Tablet	Oral	200 ug/1
Tablet	Oral	300 ug/1
Tablet	Oral	88 ug/1
Liquid	Intravenous	500 mcg
Tablet	Oral	100 mcg
Tablet	Oral	112 mcg
Tablet	Oral	125 mcg
Tablet	Oral	150 mcg
Tablet	Oral	175 mcg
Tablet	Oral	200 mcg
Tablet	Oral	25 mcg
Tablet	Oral	300 mcg
Tablet	Oral	50 mcg
Tablet	Oral	75 mcg
Tablet	Oral	88 mcg
Capsule	Oral	100 ug/1
Capsule	Oral	112 ug/1
Capsule	Oral	125 ug/1
Capsule	Oral	13 ug/1
Capsule	Oral	137 ug/1
Capsule	Oral	150 ug/1
Capsule	Oral	175 ug/1
Capsule	Oral	200 ug/1
Capsule	Oral	25 ug/1
Capsule	Oral	50 ug/1
Capsule	Oral	75 ug/1
Capsule	Oral	88 ug/1

Prices

Unit description	Cost	Unit
Levothyroxine sodium powder	159.12USD	g
Levothyroxine 200 mcg vial	24.0USD	vial
Levothyroxine 500 mcg vial	24.0USD	vial
Levoxyl 300 mcg tablet	2.34USD	tablet
Synthroid 300 mcg tablet	1.29USD	tablet
Synthroid 175 mcg tablet	1.07USD	tablet
Synthroid 200 mcg tablet	0.99USD	tablet
Synthroid 137 mcg tablet	0.87USD	tablet
Synthroid 112 mcg tablet	0.84USD	tablet
Synthroid 125 mcg tablet	0.84USD	tablet
Synthroid 150 mcg tablet	0.83USD	tablet
Levothyroxine Sodium 300 mcg tablet	0.77USD	tablet
Synthroid 100 mcg tablet	0.73USD	tablet
Synthroid 75 mcg tablet	0.72USD	tablet
Synthroid 88 mcg tablet	0.71USD	tablet
Levoxyl 200 mcg tablet	0.7USD	tablet
Levoxyl 175 mcg tablet	0.69USD	tablet
Unithroid 300 mcg tablet	0.69USD	tablet
Synthroid 50 mcg tablet	0.65USD	tablet
Levoxyl 137 mcg tablet	0.62USD	tablet
Unithroid 200 mcg tablet	0.62USD	tablet
Levoxyl 112 mcg tablet	0.61USD	tablet
Synthroid 25 mcg tablet	0.61USD	tablet
Unithroid 175 mcg tablet	0.61USD	tablet
Levoxyl 150 mcg tablet	0.59USD	tablet
Levoxyl 125 mcg tablet	0.58USD	tablet
Levothyroxine Sodium 175 mcg tablet	0.57USD	tablet
Levothyroxine Sodium 200 mcg tablet	0.57USD	tablet
Levothyroxine 175 mcg tablet	0.55USD	tablet
Unithroid 150 mcg tablet	0.55USD	tablet
Levoxyl 88 mcg tablet	0.54USD	tablet
Unithroid 112 mcg tablet	0.53USD	tablet
Unithroid 125 mcg tablet	0.53USD	tablet
Levoxyl 75 mcg tablet	0.52USD	tablet
Levothroid 300 mcg tablet	0.51USD	tablet
Levoxyl 100 mcg tablet	0.51USD	tablet
Levothyroxine Sodium 100 mcg tablet	0.5USD	tablet
Levothyroxine Sodium 150 mcg tablet	0.5USD	tablet
Levothyroxine Sodium 88 mcg tablet	0.5USD	tablet
Levoxyl 50 mcg tablet	0.49USD	tablet
Unithroid 88 mcg tablet	0.49USD	tablet
Unithroid 100 mcg tablet	0.47USD	tablet
Unithroid 75 mcg tablet	0.47USD	tablet
Levothyroxine Sodium 125 mcg tablet	0.47USD	tablet
Levothyroxine Sodium 137 mcg tablet	0.47USD	tablet
Levothyroxine Sodium 50 mcg tablet	0.47USD	tablet
Levothyroxine Sodium 75 mcg tablet	0.47USD	tablet
Levothyroxine Sodium 112 mcg tablet	0.46USD	tablet
Levothyroxine 137 mcg tablet	0.45USD	tablet
Levoxyl 25 mcg tablet	0.45USD	tablet
Levothyroxine 112 mcg tablet	0.44USD	tablet
Levothyroxine Sodium 25 mcg tablet	0.43USD	tablet
Unithroid 50 mcg tablet	0.43USD	tablet
Unithroid 25 mcg tablet	0.42USD	tablet
Unithroid direct 100 mcg tablet	0.42USD	tablet
Unithroid direct 112 mcg tablet	0.42USD	tablet
Unithroid direct 125 mcg tablet	0.42USD	tablet
Unithroid direct 150 mcg tablet	0.42USD	tablet
Unithroid direct 175 mcg tablet	0.42USD	tablet
Unithroid direct 200 mcg tablet	0.42USD	tablet
Unithroid direct 25 mcg tablet	0.42USD	tablet
Unithroid direct 300 mcg tablet	0.42USD	tablet
Unithroid direct 50 mcg tablet	0.42USD	tablet
Unithroid direct 75 mcg tablet	0.42USD	tablet
Unithroid direct 88 mcg tablet	0.42USD	tablet
Levothroid 200 mcg tablet	0.4USD	tablet
Levothroid 175 mcg tablet	0.38USD	tablet
Levothyroxine 88 mcg tablet	0.38USD	tablet
Levothroid 125 mcg tablet	0.36USD	tablet
Levothroid 150 mcg tablet	0.36USD	tablet
Levothroid 100 mcg tablet	0.35USD	tablet
Levothroid 137 mcg tablet	0.35USD	tablet
Levothroid 112 mcg tablet	0.34USD	tablet
Levothroid 75 mcg tablet	0.33USD	tablet
Levothroid 88 mcg tablet	0.33USD	tablet
Levothyroxine 300 mcg tablet	0.32USD	tablet
Levothroid 25 mcg tablet	0.31USD	tablet
Unithroid 137 mcg tablet	0.31USD	tablet
Levothroid 50 mcg tablet	0.3USD	tablet
Levothyroxine 200 mcg tablet	0.29USD	tablet
Levothyroxine 150 mcg tablet	0.24USD	tablet
Levothyroxine 125 mcg tablet	0.22USD	tablet
Levothyroxine 100 mcg tablet	0.2USD	tablet
Levothyroxine 75 mcg tablet	0.2USD	tablet
Levothyroxine 50 mcg tablet	0.18USD	tablet
Synthroid 0.137 mg Tablet	0.18USD	tablet
Levothyroxine 25 mcg tablet	0.17USD	tablet
Synthroid 0.3 mg Tablet	0.12USD	tablet
Synthroid 0.175 mg Tablet	0.11USD	tablet
Synthroid 0.075 mg Tablet	0.1USD	tablet
Synthroid 0.088 mg Tablet	0.1USD	tablet
Synthroid 0.112 mg Tablet	0.1USD	tablet
Synthroid 0.125 mg Tablet	0.1USD	tablet
Synthroid 0.025 mg Tablet	0.09USD	tablet
Synthroid 0.2 mg Tablet	0.09USD	tablet
Synthroid 0.1 mg Tablet	0.08USD	tablet
Synthroid 0.15 mg Tablet	0.08USD	tablet
Eltroxin 0.3 mg Tablet	0.07USD	tablet
Synthroid 0.05 mg Tablet	0.06USD	tablet
Eltroxin 0.2 mg Tablet	0.05USD	tablet
Eltroxin 0.1 mg Tablet	0.04USD	tablet
Eltroxin 0.15 mg Tablet	0.04USD	tablet
Eltroxin 0.05 mg Tablet	0.03USD	tablet

DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.

Patents

Patent Number	Pediatric Extension	Approved	Expires (estimated)
US7723390	No	2004-03-14	2024-03-14
US7101569	No	2003-10-02	2023-10-02
US7067148	No	2002-02-15	2022-02-15
US6555581	No	2002-02-15	2022-02-15
US6399101	No	2000-03-30	2020-03-30
US9168239	No	2012-08-29	2032-08-29
US9168238	No	2012-08-29	2032-08-29
US9006289	No	2012-10-03	2032-10-03
US7691411	No	2004-03-14	2024-03-14

Properties

State

Solid

Experimental Properties

Property	Value	Source
melting point (°C)	235.5 °C	PhysProp
water solubility	0.105 mg/mL	Not Available
logP	4	Not Available

Predicted Properties

Property	Value	Source
Water Solubility	0.00898 mg/mL	ALOGPS
logP	1.15	ALOGPS
logP	3.73	ChemAxon
logS	-4.9	ALOGPS
pKa (Strongest Acidic)	0.27	ChemAxon
pKa (Strongest Basic)	9.43	ChemAxon
Physiological Charge	0	ChemAxon
Hydrogen Acceptor Count	4	ChemAxon
Hydrogen Donor Count	3	ChemAxon
Polar Surface Area	92.78 Å²	ChemAxon
Rotatable Bond Count	5	ChemAxon
Refractivity	126.79 m³·mol^-1	ChemAxon
Polarizability	49.4 Å³	ChemAxon
Number of Rings	2	ChemAxon
Bioavailability	1	ChemAxon
Rule of Five	No	ChemAxon
Ghose Filter	No	ChemAxon
Veber's Rule	No	ChemAxon
MDDR-like Rule	No	ChemAxon

Predicted ADMET features

Property	Value	Probability
Human Intestinal Absorption	+	0.7212
Blood Brain Barrier	-	0.6886
Caco-2 permeable	-	0.653
P-glycoprotein substrate	Non-substrate	0.5321
P-glycoprotein inhibitor I	Non-inhibitor	0.9175
P-glycoprotein inhibitor II	Non-inhibitor	0.9709
Renal organic cation transporter	Non-inhibitor	0.8891
CYP450 2C9 substrate	Non-substrate	0.8309
CYP450 2D6 substrate	Non-substrate	0.9116
CYP450 3A4 substrate	Non-substrate	0.6847
CYP450 1A2 substrate	Non-inhibitor	0.5924
CYP450 2C9 inhibitor	Non-inhibitor	0.7037
CYP450 2D6 inhibitor	Non-inhibitor	0.923
CYP450 2C19 inhibitor	Non-inhibitor	0.9025
CYP450 3A4 inhibitor	Non-inhibitor	0.831
CYP450 inhibitory promiscuity	Low CYP Inhibitory Promiscuity	0.8459
Ames test	Non AMES toxic	0.7591
Carcinogenicity	Non-carcinogens	0.9148
Biodegradation	Not ready biodegradable	0.9693
Rat acute toxicity	2.7082 LD50, mol/kg	Not applicable
hERG inhibition (predictor I)	Weak inhibitor	0.9697
hERG inhibition (predictor II)	Non-inhibitor	0.8508

ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)

Spectra

Mass Spec (NIST)

Not Available

Spectra

Spectrum	Spectrum Type	Splash Key
Predicted GC-MS Spectrum - GC-MS	Predicted GC-MS	Not Available
MS/MS Spectrum - Quattro_QQQ 10V, Positive	LC-MS/MS	splash10-0ac9-0591664310-c9b7aec3184ebb20a2da
MS/MS Spectrum - Quattro_QQQ 25V, Positive	LC-MS/MS	splash10-014i-2566449540-35bb942c7bcbcfe41af7
MS/MS Spectrum - Quattro_QQQ 40V, Positive	LC-MS/MS	splash10-00xr-3375497520-9dee3cb0c153e6c6df9e
Predicted MS/MS Spectrum - 10V, Positive (Annotated)	Predicted LC-MS/MS	Not Available
Predicted MS/MS Spectrum - 20V, Positive (Annotated)	Predicted LC-MS/MS	Not Available
Predicted MS/MS Spectrum - 40V, Positive (Annotated)	Predicted LC-MS/MS	Not Available
Predicted MS/MS Spectrum - 10V, Negative (Annotated)	Predicted LC-MS/MS	Not Available
Predicted MS/MS Spectrum - 20V, Negative (Annotated)	Predicted LC-MS/MS	Not Available
Predicted MS/MS Spectrum - 40V, Negative (Annotated)	Predicted LC-MS/MS	Not Available
MS/MS Spectrum - , positive	LC-MS/MS	splash10-0059-0001001900-83ff4aafed0b73c6c7b7
1H NMR Spectrum	1D NMR	Not Applicable
[1H,13C] 2D NMR Spectrum	2D NMR	Not Applicable

Taxonomy

Description: This compound belongs to the class of organic compounds known as phenylalanine and derivatives. These are compounds containing phenylalanine or a derivative thereof resulting from reaction of phenylalanine at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom.
Kingdom: Organic compounds
Super Class: Organic acids and derivatives
Class: Carboxylic acids and derivatives
Sub Class: Amino acids, peptides, and analogues
Direct Parent: Phenylalanine and derivatives
Alternative Parents: Diphenylethers / Phenylpropanoic acids / Diarylethers / Amphetamines and derivatives / L-alpha-amino acids / Phenoxy compounds / Phenol ethers / O-iodophenols / Aralkylamines / Iodobenzenes
show 10 more
Substituents: Phenylalanine or derivatives / Diphenylether / Diaryl ether / 3-phenylpropanoic-acid / Alpha-amino acid / Amphetamine or derivatives / L-alpha-amino acid / Phenoxy compound / Phenol ether / 2-halophenol
show 27 more
Molecular Framework: Aromatic homomonocyclic compounds
External Descriptors: non-proteinogenic L-alpha-amino acid, L-phenylalanine derivative, iodophenol, 2-halophenol, thyroxine (CHEBI:18332) / thyroxine, Other amino acids, Biogenic amines (C01829)

Targets

Details1. Thyroid hormone receptor alpha

Kind: Protein
Organism: Human
Pharmacological action: Yes
Actions: Agonist

General Function: Zinc ion binding
Specific Function: Isoform Alpha-1: Nuclear hormone receptor that can act as a repressor or activator of transcription. High affinity receptor for thyroid hormones, including triiodothyronine and thyroxine.Isoform Al...
Gene Name: THRA
Uniprot ID: P10827
Uniprot Name: Thyroid hormone receptor alpha
Molecular Weight: 54815.055 Da

References

Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [PubMed:17016423]
Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [PubMed:17139284]
Bernal J: Thyroid hormone receptors in brain development and function. Nat Clin Pract Endocrinol Metab. 2007 Mar;3(3):249-59. [PubMed:17315033]
Nakajima Y, Yamada M, Horiguchi K, Satoh T, Hashimoto K, Tokuhiro E, Onigata K, Mori M: Resistance to thyroid hormone due to a novel thyroid hormone receptor mutant in a patient with hypothyroidism secondary to lingual thyroid and functional characterization of the mutant receptor. Thyroid. 2010 Aug;20(8):917-26. doi: 10.1089/thy.2009.0389. [PubMed:20615127]
Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [PubMed:11752352]

Details2. Thyroid hormone receptor beta

Kind: Protein
Organism: Human
Pharmacological action: Yes
Actions: Agonist

General Function: Zinc ion binding
Specific Function: Nuclear hormone receptor that can act as a repressor or activator of transcription. High affinity receptor for thyroid hormones, including triiodothyronine and thyroxine.
Gene Name: THRB
Uniprot ID: P10828
Uniprot Name: Thyroid hormone receptor beta
Molecular Weight: 52787.16 Da

References

Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [PubMed:17016423]
Marazuela M, Nattero L, Moure D, Garcia-Polo I, Figueroa-Vega N, Guijarro C: Thyroid hormone resistance and pituitary enlargement after thyroid ablation in a woman on levothyroxine treatment. Thyroid. 2008 Oct;18(10):1119-23. doi: 10.1089/thy.2007.0375. [PubMed:18816177]
Sivakumar T, Chaidarun S: Resistance to thyroid hormone in a patient with coexisting Graves' disease. Thyroid. 2010 Feb;20(2):213-6. doi: 10.1089/thy.2009.0175. [PubMed:20151830]
Grasberger H, Ringkananont U, Croxson M, Refetoff S: Resistance to thyroid hormone in a patient with thyroid dysgenesis. Thyroid. 2005 Jul;15(7):730-3. [PubMed:16053391]

Enzymes

Details1. Cytochrome P450 2C8

Kind: Protein
Organism: Human
Pharmacological action: Unknown
Actions: Inhibitor

General Function: Steroid hydroxylase activity
Specific Function: Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally un...
Gene Name: CYP2C8
Uniprot ID: P10632
Uniprot Name: Cytochrome P450 2C8
Molecular Weight: 55824.275 Da

References

Walsky RL, Gaman EA, Obach RS: Examination of 209 drugs for inhibition of cytochrome P450 2C8. J Clin Pharmacol. 2005 Jan;45(1):68-78. [PubMed:15601807]

Details2. Cytochrome P450 3A4

Kind: Protein
Organism: Human
Pharmacological action: Unknown
Actions: Substrate

General Function: Vitamin d3 25-hydroxylase activity
Specific Function: Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It performs a variety of oxidation react...
Gene Name: CYP3A4
Uniprot ID: P08684
Uniprot Name: Cytochrome P450 3A4
Molecular Weight: 57342.67 Da

References

Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256]

Carriers

Property	Measurement	pH	Temperature (°C)	References
IC 50 (nM)	10500	N/A	N/A	19651509

Details1. Transthyretin

Kind: Protein
Organism: Human
Pharmacological action: No

General Function: Identical protein binding
Specific Function: Thyroid hormone-binding protein. Probably transports thyroxine from the bloodstream to the brain.
Gene Name: TTR
Uniprot ID: P02766
Uniprot Name: Transthyretin
Molecular Weight: 15886.88 Da

References

Eneqvist T, Lundberg E, Karlsson A, Huang S, Santos CR, Power DM, Sauer-Eriksson AE: High resolution crystal structures of piscine transthyretin reveal different binding modes for triiodothyronine and thyroxine. J Biol Chem. 2004 Jun 18;279(25):26411-6. Epub 2004 Apr 13. [PubMed:15082720]
Palha JA: Transthyretin as a thyroid hormone carrier: function revisited. Clin Chem Lab Med. 2002 Dec;40(12):1292-300. [PubMed:12553433]

Details2. Thyroxine-binding globulin

Kind: Protein
Organism: Human
Pharmacological action: No

General Function: Serine-type endopeptidase inhibitor activity
Specific Function: Major thyroid hormone transport protein in serum.
Gene Name: SERPINA7
Uniprot ID: P05543
Uniprot Name: Thyroxine-binding globulin
Molecular Weight: 46324.12 Da

References

Palha JA: Transthyretin as a thyroid hormone carrier: function revisited. Clin Chem Lab Med. 2002 Dec;40(12):1292-300. [PubMed:12553433]

Details3. Serum albumin

Kind: Protein
Organism: Human
Pharmacological action: No

General Function: Toxic substance binding
Specific Function: Serum albumin, the main protein of plasma, has a good binding capacity for water, Ca(2+), Na(+), K(+), fatty acids, hormones, bilirubin and drugs. Its main function is the regulation of the colloid...
Gene Name: ALB
Uniprot ID: P02768
Uniprot Name: Serum albumin
Molecular Weight: 69365.94 Da

References

Palha JA: Transthyretin as a thyroid hormone carrier: function revisited. Clin Chem Lab Med. 2002 Dec;40(12):1292-300. [PubMed:12553433]

Transporters

Details1. Solute carrier organic anion transporter family member 1C1

Kind: Protein
Organism: Human
Pharmacological action: Unknown
Actions: Substrate

General Function: Thyroid hormone transmembrane transporter activity
Specific Function: Mediates the Na(+)-independent high affinity transport of organic anions such as the thyroid hormones thyroxine (T4) and rT3. Other potential substrates, such as triiodothyronine (T3), 17-beta-gluc...
Gene Name: SLCO1C1
Uniprot ID: Q9NYB5
Uniprot Name: Solute carrier organic anion transporter family member 1C1
Molecular Weight: 78695.625 Da

References

Westholm DE, Stenehjem DD, Rumbley JN, Drewes LR, Anderson GW: Competitive inhibition of organic anion transporting polypeptide 1c1-mediated thyroxine transport by the fenamate class of nonsteroidal antiinflammatory drugs. Endocrinology. 2009 Feb;150(2):1025-32. doi: 10.1210/en.2008-0188. Epub 2008 Oct 9. [PubMed:18845642]
Berman HM, Westbrook J, Feng Z, Gilliland G, Bhat TN, Weissig H, Shindyalov IN, Bourne PE: The Protein Data Bank. Nucleic Acids Res. 2000 Jan 1;28(1):235-42. [PubMed:10592235]
Pizzagalli F, Hagenbuch B, Stieger B, Klenk U, Folkers G, Meier PJ: Identification of a novel human organic anion transporting polypeptide as a high affinity thyroxine transporter. Mol Endocrinol. 2002 Oct;16(10):2283-96. [PubMed:12351693]

Details2. Monocarboxylate transporter 8

Kind: Protein
Organism: Human
Pharmacological action: Unknown
Actions: Inhibitor

General Function: Transporter activity
Specific Function: Very active and specific thyroid hormone transporter. Stimulates cellular uptake of thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (rT3) and diidothyronine. Does not transport Leu,...
Gene Name: SLC16A2
Uniprot ID: P36021
Uniprot Name: Monocarboxylate transporter 8
Molecular Weight: 59510.86 Da

References

Friesema EC, Ganguly S, Abdalla A, Manning Fox JE, Halestrap AP, Visser TJ: Identification of monocarboxylate transporter 8 as a specific thyroid hormone transporter. J Biol Chem. 2003 Oct 10;278(41):40128-35. Epub 2003 Jul 18. [PubMed:12871948]

Details3. Multidrug resistance protein 1

Kind: Protein
Organism: Human
Pharmacological action: Unknown
Actions: Inducer

General Function: Xenobiotic-transporting atpase activity
Specific Function: Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells.
Gene Name: ABCB1
Uniprot ID: P08183
Uniprot Name: Multidrug resistance protein 1
Molecular Weight: 141477.255 Da

References

Siegmund W, Altmannsberger S, Paneitz A, Hecker U, Zschiesche M, Franke G, Meng W, Warzok R, Schroeder E, Sperker B, Terhaag B, Cascorbi I, Kroemer HK: Effect of levothyroxine administration on intestinal P-glycoprotein expression: consequences for drug disposition. Clin Pharmacol Ther. 2002 Sep;72(3):256-64. [PubMed:12235446]

Details4. Solute carrier organic anion transporter family member 1A2

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Sodium-independent organic anion transmembrane transporter activity
Specific Function: Mediates the Na(+)-independent transport of organic anions such as sulfobromophthalein (BSP) and conjugated (taurocholate) and unconjugated (cholate) bile acids (By similarity). Selectively inhibit...
Gene Name: SLCO1A2
Uniprot ID: P46721
Uniprot Name: Solute carrier organic anion transporter family member 1A2
Molecular Weight: 74144.105 Da

References

Kullak-Ublick GA, Ismair MG, Stieger B, Landmann L, Huber R, Pizzagalli F, Fattinger K, Meier PJ, Hagenbuch B: Organic anion-transporting polypeptide B (OATP-B) and its functional comparison with three other OATPs of human liver. Gastroenterology. 2001 Feb;120(2):525-33. [PubMed:11159893]

Details5. Solute carrier organic anion transporter family member 1B1

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Sodium-independent organic anion transmembrane transporter activity
Specific Function: Mediates the Na(+)-independent uptake of organic anions such as pravastatin, taurocholate, methotrexate, dehydroepiandrosterone sulfate, 17-beta-glucuronosyl estradiol, estrone sulfate, prostagland...
Gene Name: SLCO1B1
Uniprot ID: Q9Y6L6
Uniprot Name: Solute carrier organic anion transporter family member 1B1
Molecular Weight: 76447.99 Da

References

Kullak-Ublick GA, Ismair MG, Stieger B, Landmann L, Huber R, Pizzagalli F, Fattinger K, Meier PJ, Hagenbuch B: Organic anion-transporting polypeptide B (OATP-B) and its functional comparison with three other OATPs of human liver. Gastroenterology. 2001 Feb;120(2):525-33. [PubMed:11159893]

Details6. Solute carrier organic anion transporter family member 1B3

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Sodium-independent organic anion transmembrane transporter activity
Specific Function: Mediates the Na(+)-independent uptake of organic anions such as 17-beta-glucuronosyl estradiol, taurocholate, triiodothyronine (T3), leukotriene C4, dehydroepiandrosterone sulfate (DHEAS), methotre...
Gene Name: SLCO1B3
Uniprot ID: Q9NPD5
Uniprot Name: Solute carrier organic anion transporter family member 1B3
Molecular Weight: 77402.175 Da

References

Kullak-Ublick GA, Ismair MG, Stieger B, Landmann L, Huber R, Pizzagalli F, Fattinger K, Meier PJ, Hagenbuch B: Organic anion-transporting polypeptide B (OATP-B) and its functional comparison with three other OATPs of human liver. Gastroenterology. 2001 Feb;120(2):525-33. [PubMed:11159893]

Details7. Solute carrier organic anion transporter family member 4A1

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Thyroid hormone transmembrane transporter activity
Specific Function: Mediates the Na(+)-independent transport of organic anions such as the thyroid hormones T3 (triiodo-L-thyronine), T4 (thyroxine) and rT3, and of estrone-3-sulfate and taurocholate.
Gene Name: SLCO4A1
Uniprot ID: Q96BD0
Uniprot Name: Solute carrier organic anion transporter family member 4A1
Molecular Weight: 77192.505 Da

References

Fujiwara K, Adachi H, Nishio T, Unno M, Tokui T, Okabe M, Onogawa T, Suzuki T, Asano N, Tanemoto M, Seki M, Shiiba K, Suzuki M, Kondo Y, Nunoki K, Shimosegawa T, Iinuma K, Ito S, Matsuno S, Abe T: Identification of thyroid hormone transporters in humans: different molecules are involved in a tissue-specific manner. Endocrinology. 2001 May;142(5):2005-12. [PubMed:11316767]

Details8. Solute carrier organic anion transporter family member 4C1

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Sodium-independent organic anion transmembrane transporter activity
Specific Function: Organic anion transporter, capable of transporting pharmacological substances such as digoxin, ouabain, thyroxine, methotrexate and cAMP. May participate in the regulation of membrane transport of ...
Gene Name: SLCO4C1
Uniprot ID: Q6ZQN7
Uniprot Name: Solute carrier organic anion transporter family member 4C1
Molecular Weight: 78947.525 Da

References

Mikkaichi T, Suzuki T, Onogawa T, Tanemoto M, Mizutamari H, Okada M, Chaki T, Masuda S, Tokui T, Eto N, Abe M, Satoh F, Unno M, Hishinuma T, Inui K, Ito S, Goto J, Abe T: Isolation and characterization of a digoxin transporter and its rat homologue expressed in the kidney. Proc Natl Acad Sci U S A. 2004 Mar 9;101(10):3569-74. Epub 2004 Mar 1. [PubMed:14993604]

Details9. Large neutral amino acids transporter small subunit 1

Kind: Protein
Organism: Human
Pharmacological action: Unknown

General Function: Peptide antigen binding
Specific Function: Sodium-independent, high-affinity transport of large neutral amino acids such as phenylalanine, tyrosine, leucine, arginine and tryptophan, when associated with SLC3A2/4F2hc. Involved in cellular a...
Gene Name: SLC7A5
Uniprot ID: Q01650
Uniprot Name: Large neutral amino acids transporter small subunit 1
Molecular Weight: 55009.62 Da

References

Uchino H, Kanai Y, Kim DK, Wempe MF, Chairoungdua A, Morimoto E, Anders MW, Endou H: Transport of amino acid-related compounds mediated by L-type amino acid transporter 1 (LAT1): insights into the mechanisms of substrate recognition. Mol Pharmacol. 2002 Apr;61(4):729-37. [PubMed:11901210]

Drug created on June 13, 2005 07:24 / Updated on October 21, 2017 09:35

Levothyroxine

Identification

Structure for DB00451 (Levothyroxine)

Pharmacology

Interactions

References

Clinical Trials

Pharmacoeconomics

Properties

Spectra

Taxonomy

Targets

References

References

Enzymes

References

References

Carriers

References

References

References

Transporters

References

References

References

References

References

References

References

References

References