Identification

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Name
Sildenafil
Accession Number
DB00203  (APRD00556)
Type
Small Molecule
Groups
Approved, Investigational
Description

In eliciting its mechanism of action, sildenafil ultimately prevents or minimizes the breakdown of cyclic guanosine monophosphate (cGMP) by inhibiting cGMP specific phosphodiesterase type 5 (PDE5) 11,12,13,14,15,16,8,9. The result of doing so allows cGMP present in both the penis and pulmonary vasculature to elicit smooth muscle relaxation and vasodilation that subsequently facilitates relief in pulmonary arterial hypertension and the increased flow of blood into the spongy erectile tissue of the penis that consequently allows it to grow in size and become erect and rigid 11,12,13,14,15,16,8,9.

Interestingly enough, it is precisely via this mechanism why sildenafil was at first researched as a potential treatment for angina - or chest pain associated with inadequate blood flow to the heart - before being serendipitously indicated for treating erectile dysfunction in the late 1980s 7. Nevertheless, it is because of this mechanism that sildenafil is also indicated for treating pulmonary arterial hypertension but is also additionally notorious for interacting with various anti-anginal or anti-hypertensive agents to develop potentially rapid, excessive, and/or fatal hypotensive crises 4,5,6.

Regardless, sildenafil, among a variety of other similar or related PDE5 inhibitors, has become a common and effective treatment for erectile dysfunction and since its formal approval for medical use in the public in 1998 7, continues to see millions of prescriptions written for it internationally. Although the medication has historically been most popularly recognized as Pfizer's brand name Viagra, sildenafil is currently available generically and even as a non-prescription over the counter medication in some countries 10.

Structure
Thumb
Synonyms
  • 1-((3-(4,7-Dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo(4,3-d)pyrimidin-5-yl)-4-ethoxyphenyl)sulfonyl)-4-methylpiperazine
  • Sildenafil
  • Sildenafilo
External IDs
HIP-0908 / HIP0908
Product Ingredients
IngredientUNIICASInChI Key
Sildenafil citrateBW9B0ZE037171599-83-0DEIYFTQMQPDXOT-UHFFFAOYSA-N
Product Images
Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
Act SildenafilTabletOralActavis Pharma Company2012-11-082018-06-26Canada
Act SildenafilTabletOralActavis Pharma Company2012-11-082018-06-26Canada
Act SildenafilTabletOralActavis Pharma Company2012-11-082018-06-26Canada
M-sildenafilTabletOralMantra Pharma Inc2015-06-04Not applicableCanada
M-sildenafilTabletOralMantra Pharma IncNot applicableNot applicableCanada
M-sildenafilTabletOralMantra Pharma IncNot applicableNot applicableCanada
Nra-sildenafilTabletOralNora Pharma IncNot applicableNot applicableCanada
Nra-sildenafilTabletOralNora Pharma IncNot applicableNot applicableCanada
Nra-sildenafilTabletOralNora Pharma Inc2018-12-04Not applicableCanada
Prz-sildenafilTabletOralPharmaris Canada Inc2018-05-02Not applicableCanada
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

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  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

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Generic Prescription Products
NameDosageStrengthRouteLabellerMarketing StartMarketing End
Accel-sildenafilTabletOralAccel Pharma Inc2019-08-15Not applicableCanada
Accel-sildenafilTabletOralAccel Pharma Inc2019-08-15Not applicableCanada
Accel-sildenafilTabletOralAccel Pharma Inc2019-08-15Not applicableCanada
Ag-sildenafilTabletOralAngita Pharma Inc.2018-12-21Not applicableCanada
Ag-sildenafilTabletOralAngita Pharma Inc.2018-12-21Not applicableCanada
Ag-sildenafilTabletOralAngita Pharma Inc.2018-12-21Not applicableCanada
Apo-sildenafilTabletOralApotex Corporation2012-11-14Not applicableCanada
Apo-sildenafilTabletOralApotex Corporation2012-11-09Not applicableCanada
Apo-sildenafilTabletOralApotex Corporation2012-11-14Not applicableCanada
Apo-sildenafil RTabletOralApotex Corporation2013-12-23Not applicableCanada
Additional Data Available
  • Application Number
    Application Number

    A unique ID assigned by the FDA when a product is submitted for approval by the labeller.

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  • Product Code
    Product Code

    A governmentally-recognized ID which uniquely identifies the product within its regulatory market.

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Categories
UNII
3M7OB98Y7H
CAS number
139755-83-2
Weight
Average: 474.576
Monoisotopic: 474.204924168
Chemical Formula
C22H30N6O4S
InChI Key
BNRNXUUZRGQAQC-UHFFFAOYSA-N
InChI
InChI=1S/C22H30N6O4S/c1-5-7-17-19-20(27(4)25-17)22(29)24-21(23-19)16-14-15(8-9-18(16)32-6-2)33(30,31)28-12-10-26(3)11-13-28/h8-9,14H,5-7,10-13H2,1-4H3,(H,23,24,29)
IUPAC Name
5-{2-ethoxy-5-[(4-methylpiperazin-1-yl)sulfonyl]phenyl}-1-methyl-3-propyl-1H,4H,7H-pyrazolo[4,3-d]pyrimidin-7-one
SMILES
CCCC1=NN(C)C2=C1NC(=NC2=O)C1=C(OCC)C=CC(=C1)S(=O)(=O)N1CCN(C)CC1

Pharmacology

Indication

Sildenafil is a phosphodiesterase-5 (PDE5) inhibitor that is predominantly employed for two primary indications:

(1) the treatment of erectile dysfunction 5,8,12,13,16; and

(2) treatment of pulmonary hypertension, where: a) the US FDA specifically indicates sildenafil for the treatment of pulmonary arterial hypertension (PAH) (WHO Group I) in adults to improve exercise ability and delay clinical worsening 11. The delay in clinical worsening was demonstrated when sildenafil was added to background epoprostenol therapy 11. Studies establishing effectiveness were short-term (12 to 16 weeks), and included predominately patients with New York Heart Association (NYHA) Functional Class II-III symptoms and idiopathic etiology (71%) or associated with connective tissue disease (CTD) (25%) 11;

b) the Canadian product monograph specifically indicates sildenafil for the treatment of primary pulmonary arterial hypertension (PPH) or pulmonary hypertension secondary to connective tissue disease (CTD) in adult patients with WHO functional class II or III who have not responded to conventional therapy 14. In addition, improvement in exercise ability and delay in clinical worsening was demonstrated in adult patients who were already stabilized on background epoprostenol therapy 14; and

c) the EMA product information specifically indicates sildenafil for the treatment of adult patients with pulmonary arterial hypertension classified as WHO functional class II and III, to improve exercise capacity 15. Efficacy has been shown in primary pulmonary hypertension and pulmonary hypertension associated with connective tissue disease 15. The EMA label also indicates sildenafil for the treatment of pediatric patients aged 1 year to 17 years old with pulmonary arterial hypertension 15. Efficacy in terms of improvement of exercise capacity or pulmonary hemodynamics has been shown in primary pulmonary hypertension and pulmonary hypertension associated with congenital heart disease 15.

Associated Conditions
Pharmacodynamics

In vitro studies have shown that sildenafil is selective for phosphodiesterase-5 (PDE5) 11,12,13,14,15,16,8,9. Its effect is more potent on PDE5 than on other known phosphodiesterases 11,12,13,14,15,16,8,9. In particular, there is a 10-times selectivity over PDE6 which is involved in the phototransduction pathway in the retina 11,12,13,14,15,16,8,9. There is an 80-times selectivity over PDE1, and over 700-times over PDE 2, 3, 4, 7, 8, 9, 10 and 11 11,12,13,14,15,16,8,9. And finally, sildenafil has greater than 4,000-times selectivity for PDE5 over PDE3, the cAMP-specific phosphodiesterase isoform involved in the control of cardiac contractility 11,12,13,14,15,16,8,9.

In eight double-blind, placebo-controlled crossover studies of patients with either organic or psychogenic erectile dysfunction, sexual stimulation resulted in improved erections, as assessed by an objective measurement of hardness and duration of erections (via the use of RigiScan®), after sildenafil administration compared with placebo 11,12,13,14,15,16,8,9. Most studies assessed the efficacy of sildenafil approximately 60 minutes post-dose 11,12,13,14,15,16,8,9. The erectile response, as assessed by RigiScan®, generally increased with increasing sildenafil dose and plasma concentration 11,12,13,14,15,16,8,9. The time course of effect was examined in one study, showing an effect for up to 4 hours but the response was diminished compared to 2 hours 11,12,13,14,15,16,8,9.

Sildenafil causes mild and transient decreases in systemic blood pressure which, in the majority of cases, do not translate into clinical effects 11,12,13,14,15,16,8,9. After chronic dosing of 80 mg, three times a day to patients with systemic hypertension the mean change from baseline in systolic and diastolic blood pressure was a decrease of 9.4 mmHg and 9.1 mmHg respectively 11,12,13,14,15,16,8,9. After chronic dosing of 80 mg, three times a day to patients with pulmonary arterial hypertension lesser effects in blood pressure reduction were observed (a reduction in both systolic and diastolic pressure of 2 mmHg)11,12,13,14,15,16,8,9 . At the recommended dose of 20 mg three times a day no reductions in systolic or diastolic pressure were seen 11,12,13,14,15,16,8,9.

Single oral doses of sildenafil up to 100 mg in healthy volunteers produced no clinically relevant effects on ECG 11,12,13,14,15,16,8,9. After chronic dosing of 80 mg three times a day to patients with pulmonary arterial hypertension no clinically relevant effects on the ECG were reported either 11,12,13,14,15,16,8,9.

In a study of the hemodynamic effects of a single oral 100 mg dose of sildenafil in 14 patients with severe coronary artery disease (CAD) (> 70 % stenosis of at least one coronary artery), the mean resting systolic and diastolic blood pressures decreased by 7 % and 6 % respectively compared to baseline 11,12,13,14,15,16,8,9. Mean pulmonary systolic blood pressure decreased by 9% 11,12,13,14,15,16,8,9. Sildenafil showed no effect on cardiac output and did not impair blood flow through the stenosed coronary arteries 11,12,13,14,15,16,8,9.

Mild and transient differences in color discrimination (blue/green) were detected in some subjects using the Farnsworth-Munsell 100 hue test at 1 hour following a 100 mg dose, with no effects evident after 2 hours post-dose 11,12,13,14,15,16,8,9. The postulated mechanism for this change in color discrimination is related to inhibition of PDE6, which is involved in the phototransduction cascade of the retina 11,12,13,14,15,16,8,9. Sildenafil has no effect on visual acuity or contrast sensitivity. In a small size placebo-controlled study of patients with documented early age-related macular degeneration (n = 9), sildenafil (single dose, 100 mg) demonstrated no significant changes in visual tests conducted (which included visual acuity, Amsler grid, color discrimination simulated traffic light, and the Humphrey perimeter and photostress test) 11,12,13,14,15,16,8,9.

Mechanism of action

Sildenafil is an oral therapy for erectile dysfunction 5,12,13,16,8. In the natural setting, i.e. with sexual stimulation, it restores impaired erectile function by increasing blood flow to the penis 5,12,13,16,8.

The physiological mechanism responsible for the erection of the penis involves the release of nitric oxide (NO) in the corpus cavernosum during sexual stimulation 5,12,13,16,8. Nitric oxide then activates the enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP), producing smooth muscle relaxation in the corpus cavernosum and allowing inflow of blood 5,12,13,16,8.

Sildenafil is a potent and selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) in the corpus cavernosum, where PDE5 is responsible for degradation of cGMP 5,12,13,16,8. Sildenafil has a peripheral site of action on erections 5,12,13,16,8. Sildenafil has no direct relaxant effect on isolated human corpus cavernosum but potently enhances the relaxant effect of NO on this tissue 5,12,13,16,8. When the NO/cGMP pathway is activated, as occurs with sexual stimulation, inhibition of PDE5 by sildenafil results in increased corpus cavernosum levels of cGMP 5,12,13,16,8. Therefore sexual stimulation is required in order for sildenafil to produce its intended beneficial pharmacological effects 5,12,13,16,8.

Moreover, apart from the presence of PDE5 in the corpus cavernosum of the penis, PDE5 is also present in the pulmonary vasculature 4,11,14,15,9. Sildenafil, therefore, increases cGMP within pulmonary vascular smooth muscle cells resulting in relaxation 4,11,14,15,9. In patients with pulmonary arterial hypertension, this can lead to vasodilation of the pulmonary vascular bed and, to a lesser degree, vasodilatation in the systemic circulation 4,11,14,15,9.

TargetActionsOrganism
AcGMP-specific 3',5'-cyclic phosphodiesterase
inhibitor
Humans
NRetinal rod rhodopsin-sensitive cGMP 3',5'-cyclic phosphodiesterase subunit gamma
inhibitor
Humans
NRetinal cone rhodopsin-sensitive cGMP 3',5'-cyclic phosphodiesterase subunit gamma
inhibitor
Humans
Additional Data Available
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Absorption

Sildenafil is known to be quickly absorbed, with maximum plasma concentrations being observed within 30-120 minutes (with a median of 60 minutes) of oral administration in a fasting patient 11,12,13,14,15,16,8,9. Moreover, the mean absolute bioavailability observed for sildenafil is about 41% (from a range of 25-63%) 11,12,13,14,15,16,8,9. In particular, after oral three times a day dosing of sildenafil, the AUC and Cmax increase in proportion with dose over the recommended dosage range of 25-100 mg 11,12,13,14,15,16,8,9.

When used in pulmonary arterial hypertension patients, however, the oral bioavailability of sildenafil after a dosing regimen of 80 mg three times a day, was on average 43% greater than compared to the lower doses 11,12,13,14,15,16,8,9.

Finally, if sildenafil is administered orally with food, the rate of absorption is observed to be decreased with a mean delay in Tmax of about 60 minutes and a mean decrease in Cmax of approximately 29% 11,12,13,14,15,16,8,9. Regardless, the extent of absorption is not observed to be significantly affected as the recorded AUC decreased by only about 11 % 11,12,13,14,15,16,8,9.

Volume of distribution

The mean steady-state volume of distribution documented for sildenafil is approximately 105 L - a value which suggests the medication undergoes distribution into the tissues 11,12,13,14,15,16,8,9.

Protein binding

It is generally observed that sildenafil and its main circulating N-desmethyl metabolite are both estimated to be about 96% bound to plasma proteins 11,12,13,14,15,16,8,9. Nevertheless, it has been determined that protein binding for sildenafil is independent of total drug concentrations 11,12,13,14,15,16,8,9.

Metabolism

The metabolism of sildenafil is facilitated primarily by the CYP3A4 hepatic microsomal isoenzymes and to a minor extent, via the CYP2C9 hepatic isoenzymes 6,11,12,13,14,15,16,8,9. The predominant circulating metabolite results from the N-demethylation of sildenafil 6,11,12,13,14,15,16,8,9. This particular resultant metabolite possesses a phosphodiesterase selectivity that is similar to the parent sildenafil molecule and a corresponding in vitro potency for PDE5 that is approximately 50% that of the parent drug 6,11,12,13,14,15,16,8,9. Moreover, plasma concentrations of the metabolite are about 40% of those recorded for sildenafil, a percentage that accounts for about 20% of sildenafil’s pharmacologic effects 6,11,12,13,14,15,16,8,9. This primary N-desmethyl metabolite of sildenafil also undergoes further metabolism, with a terminal half-life of about 4 hours 6,11,12,13,14,15,16,8,9.

In patients with pulmonary arterial hypertension, plasma concentrations of the primary N-desmethyl metabolite are about 72% those of the original parent sildenafil molecule after a regimen of 20 mg three times a day - which is consequently responsible for about a 36% contribution to sildenafil’s overall pharmacological effects 6,11,12,13,14,15,16,8,9.

Route of elimination

After either oral or intravenous administration, sildenafil is excreted as metabolites predominantly in the feces (approximately 80% of the administered oral dose) and to a lesser extent in the urine (approximately 13% of the administered oral dose) 11,12,13,14,15,16,8,9.

Half life

The terminal phase half-life observed for sildenafil is approximately 3 to 5 hours 11,12,13,14,15,16,8,9.

Clearance

The total body clearance documented for sildenafil is 41 L/h 11,12,13,14,15,16,8,9.

Toxicity

In single-dose volunteer studies of doses up to 800 mg, adverse reactions were similar to those seen at lower doses, but the incidence rates and severities were increased 11,12,13,14,15,16,8,9. Doses of 200 mg did not result in increased efficacy but the incidence of adverse reaction (headache, flushing, dizziness, dyspepsia, nasal congestion, altered vision) was increased 11,12,13,14,15,16,8,9.

Due to the lack of data on the effect of sildenafil indicated for the treatment of pulmonary arterial hypertension (PAH) in pregnant women, sildenafil is not recommended for women of childbearing potential unless also using appropriate contraceptive measures 11,14,15,9.

The safety and efficacy of sildenafil indicated for treating PAH in a woman during labor and delivery have not been studied 11,14,15,9. Caution should ultimately be exercised when sildenafil is administered to nursing women as it is not known if sildenafil or its metabolites are excreted in human breast milk 11,14,15,9.

The safety and efficacy of sildenafil for the treatment of PAH in children below 1 year of age has not been established as no data is available 15.

Clinical experience with the elderly population in the use of sildenafil for the treatment of PAH has been varied. Some reports suggest that there are no identified differences in responses between elderly and younger patients 11 while others have documented that clinical efficacy as measured by 6-minute walk distance could be less in elderly patients 9. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy 11.

Conversely, when sildenafil was used to treat erectile dysfunction in healthy elderly volunteers (65 years or over), a reduced clearance of sildenafil was observed 12,8. This reduction resulted in about 90% higher plasma concentrations of sildenafil and the active N-desmethyl metabolite compared to those seen in healthy younger volunteers (18-45 years) 12,8. Due to age-differences in plasma protein binding, the corresponding increase in free sildenafil plasma concentration was approximately 40% 12,8.

Sildenafil was not carcinogenic when administered to rats for 24 months at a dose resulting in total systemic drug exposure (AUCs) for unbound sildenafil and its major metabolite of 29- and 42- times, for male and female rats, respectively, the exposures observed in human males given the Maximum Recommended Human Dose (MRHD) of 100 mg 11,12,13,14,15,16,8,9. Sildenafil was not carcinogenic when administered to mice for 18-21 months at dosages up to the Maximum Tolerated Dose (MTD) of 10 mg/kg/day, approximately 0.6 times the MRHD on a mg/m2 basis 11,12,13,14,15,16,8,9.

Sildenafil was negative in in vitro bacterial and Chinese hamster ovary cell assays to detect mutagenicity, and in vitro human lymphocytes and in vivo mouse micronucleus assays to detect clastogenicity 11,12,13,14,15,16,8,9.

There was no impairment of fertility in rats given sildenafil up to 60 mg/kg/day for 36 days to females and 102 days to males, a dose producing an AUC value of more than 25 times the human male AUC 11,12,13,14,15,16,8,9.

Affected organisms
  • Humans and other mammals
Pathways
Not Available
Pharmacogenomic Effects/ADRs
Interacting Gene/EnzymeAllele nameGenotype(s)Defining Change(s)Type(s)DescriptionDetails
Angiotensin-converting enzyme---Not AvailableAlu insertions / Alu insertions  … show all Effect Directly StudiedPatients with this genotype have increased frequency of positive erectile response when using sildenafil to treat erectile dysfunctionDetails
Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-3---(T;T)T allele, homozygoteEffect Directly StudiedPatients with this genotype have increased frequency of positive erectile response when using sildenafil to treat erectile dysfunctionDetails

Interactions

Drug Interactions
This information should not be interpreted without the help of a healthcare provider. If you believe you are experiencing an interaction, contact a healthcare provider immediately. The absence of an interaction does not necessarily mean no interactions exist.
DrugInteraction
(R)-warfarinThe risk or severity of hemorrhage can be increased when (R)-warfarin is combined with Sildenafil.
(S)-WarfarinThe risk or severity of hemorrhage can be increased when (S)-Warfarin is combined with Sildenafil.
1-(2-Phenylethyl)-4-phenyl-4-acetoxypiperidineThe metabolism of Sildenafil can be decreased when combined with 1-(2-Phenylethyl)-4-phenyl-4-acetoxypiperidine.
2,4-thiazolidinedioneThe therapeutic efficacy of 2,4-thiazolidinedione can be increased when used in combination with Sildenafil.
4-hydroxycoumarinThe risk or severity of hemorrhage can be increased when 4-hydroxycoumarin is combined with Sildenafil.
4-MethoxyamphetamineThe metabolism of 4-Methoxyamphetamine can be decreased when combined with Sildenafil.
5-methoxy-N,N-dimethyltryptamineThe metabolism of 5-methoxy-N,N-dimethyltryptamine can be decreased when combined with Sildenafil.
6-Deoxyerythronolide BThe metabolism of Sildenafil can be decreased when combined with 6-Deoxyerythronolide B.
7-ethyl-10-hydroxycamptothecinThe metabolism of Sildenafil can be decreased when combined with 7-ethyl-10-hydroxycamptothecin.
9-aminocamptothecinThe metabolism of Sildenafil can be decreased when combined with 9-aminocamptothecin.
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Food Interactions
Not Available

References

Synthesis Reference

Peter James Dunn, Albert Shaw Wood, "Process for preparing sildenafil." U.S. Patent US5955611, issued December, 1994.

US5955611
General References
  1. Boolell M, Allen MJ, Ballard SA, Gepi-Attee S, Muirhead GJ, Naylor AM, Osterloh IH, Gingell C: Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction. Int J Impot Res. 1996 Jun;8(2):47-52. [PubMed:8858389]
  2. Cheitlin MD, Hutter AM Jr, Brindis RG, Ganz P, Kaul S, Russell RO Jr, Zusman RM: ACC/AHA expert consensus document. Use of sildenafil (Viagra) in patients with cardiovascular disease. American College of Cardiology/American Heart Association. J Am Coll Cardiol. 1999 Jan;33(1):273-82. [PubMed:9935041]
  3. Fries R, Shariat K, von Wilmowsky H, Bohm M: Sildenafil in the treatment of Raynaud's phenomenon resistant to vasodilatory therapy. Circulation. 2005 Nov 8;112(19):2980-5. [PubMed:16275885]
  4. Unegbu C, Noje C, Coulson JD, Segal JB, Romer L: Pulmonary Hypertension Therapy and a Systematic Review of Efficacy and Safety of PDE-5 Inhibitors. Pediatrics. 2017 Mar;139(3). pii: peds.2016-1450. doi: 10.1542/peds.2016-1450. [PubMed:28235796]
  5. Gong B, Ma M, Xie W, Yang X, Huang Y, Sun T, Luo Y, Huang J: Direct comparison of tadalafil with sildenafil for the treatment of erectile dysfunction: a systematic review and meta-analysis. Int Urol Nephrol. 2017 Oct;49(10):1731-1740. doi: 10.1007/s11255-017-1644-5. Epub 2017 Jul 24. [PubMed:28741090]
  6. Nichols DJ, Muirhead GJ, Harness JA: Pharmacokinetics of sildenafil after single oral doses in healthy male subjects: absolute bioavailability, food effects and dose proportionality. Br J Clin Pharmacol. 2002;53 Suppl 1:5S-12S. [PubMed:11879254]
  7. Goldstein I, Burnett AL, Rosen RC, Park PW, Stecher VJ: The Serendipitous Story of Sildenafil: An Unexpected Oral Therapy for Erectile Dysfunction. Sex Med Rev. 2019 Jan;7(1):115-128. doi: 10.1016/j.sxmr.2018.06.005. Epub 2018 Oct 6. [PubMed:30301707]
  8. Electronic Medicines Compendium: Sildenafil 25mg, 50mg, 100mg film-coated tablets Monograph [Link]
  9. Electronic Medicines Compendium: Revatio (sildenafil citrate) 20 mg film-coated tablets Monograph [Link]
  10. Forbes: With Viagra Now Available Over-The-Counter In The U.K., Will The U.S. Follow Suit? [Link]
  11. Revatio (sildenafil) FDA Label [File]
  12. Viagra (sildenafil citrate) FDA Label [File]
  13. Viagra (sildenafil citrate) Tablets 25 mg, 50 mg, and 100 mg Canadian Product Monograph [File]
  14. Revatio (sildenafil citrate) Canadian Product Monograph [File]
  15. Revatio (sildenafil citrate) EMA Label [File]
  16. Viagra (sildenafil citrate) EMA Label [File]
External Links
Human Metabolome Database
HMDB0005039
KEGG Drug
D08514
KEGG Compound
C07259
PubChem Compound
5212
PubChem Substance
46508371
ChemSpider
5023
BindingDB
14390
ChEBI
9139
ChEMBL
CHEMBL192
Therapeutic Targets Database
DAP000614
PharmGKB
PA451346
HET
VIA
RxList
RxList Drug Page
Drugs.com
Drugs.com Drug Page
PDRhealth
PDRhealth Drug Page
Wikipedia
Sildenafil
ATC Codes
G04BE03 — SildenafilG01AE10 — Combinations of sulfonamides
AHFS Codes
  • 24:12.12 — Phosphodiesterase Type 5 Inhibitors
PDB Entries
1tbf / 1udt / 1xos / 2h42 / 3jwq
FDA label
Download (80.5 KB)
MSDS
Download (37.1 KB)

Clinical Trials

Clinical Trials
PhaseStatusPurposeConditionsCount
0CompletedOtherCongenital Heart Disease (CHD) / Liver Cirrhosis1
0CompletedPreventionImmersion Pulmonary Edema (IPE) / Swimming Induced Pulmonary Edema (SIPE)1
0CompletedTreatmentDermatomyositis / Raynaud Phenomenon Due to Trauma / Raynaud's Phenomenon / System; Sclerosis / Systemic Lupus Erythematosus (SLE) / Ultrasound Therapy; Complications1
0Not Yet RecruitingBasic ScienceIntrapulmonary Arteriovenous Anastamosis / Patent Foramen Ovale (PFO)1
0RecruitingBasic ScienceMigraine With Aura1
0RecruitingPreventionHand Foot Skin Reaction1
0RecruitingTreatmentHemolysis / Thrombotic events1
0TerminatedTreatmentErectile Dysfunction / Hypogonadism1
1Active Not RecruitingTreatmentNeonatal Encephalopathy1
1Active Not RecruitingTreatmentTumors, Solid1
1CompletedNot AvailableErectile Dysfunction1
1CompletedNot AvailableFemale Sexual Health1
1CompletedNot AvailableNone Volunteer1
1CompletedBasic ScienceErectile Dysfunction4
1CompletedBasic ScienceErectile Dysfunction / Prostatic Hyperplasia / Urinary Bladder, Overactive1
1CompletedBasic ScienceGenetic Polymorphic CYP3A5 / Healthy Volunteers / Pharmacokinetics of Three PDE5Is1
1CompletedBasic ScienceHealthy Volunteers3
1CompletedBasic ScienceMicrovascular coronary artery disease1
1CompletedBasic SciencePersistent Pulmonary Hypertension of the Newborn1
1CompletedDiagnosticTraumatic Brain Injury (TBI)1
1CompletedOtherHealthy Volunteers1
1CompletedPreventionAcute Kidney Injury (AKI)1
1CompletedPreventionHealthy Volunteers1
1CompletedSupportive CareKidney Tumors1
1CompletedTreatmentBreast Cancer / Gastrointestinal Cancers / Genitourinary Cancers / Gynecologic Cancers / Sarcomas1
1CompletedTreatmentDuchenne's Muscular Dystrophy (DMD)1
1CompletedTreatmentErectile Dysfunction2
1CompletedTreatmentHand Foot Syndrome / Palmar Plantar Erythrodysesthesia1
1CompletedTreatmentHealthy Volunteers2
1CompletedTreatmentHeart Diseases1
1CompletedTreatmentHepatitis C Viral Infection1
1CompletedTreatmentHigh Blood Pressure (Hypertension)1
1CompletedTreatmentHypertension, Pulmonary [C08.381.423] / Pulmonary Hypertension (PH)1
1CompletedTreatmentPulmonary Arterial Hypertention1
1CompletedTreatmentRecurrent Miscarriages1
1CompletedTreatmentSickle Cell Disorders1
1Not Yet RecruitingOtherErectile Dysfunction1
1RecruitingPreventionLabor Preterm Requiring Hospitalization1
1RecruitingTreatmentCerebral Vasospasm / Subarachnoid Hemorrhage1
1RecruitingTreatmentCombination of Oral Anticoagulation Therapy and Sildenafil / Intermediate-high Risk / Pulmonary Embolism1
1RecruitingTreatmentMild Traumatic Brain Injury (MTBI) / Post-Concussion Syndrome / Traumatic Brain Injury (TBI)1
1RecruitingTreatmentUrinary Incontinence (UI)1
1TerminatedBasic ScienceCongestive Heart Failure / Renal Dysfunction1
1TerminatedTreatmentLiver Cirrhosis1
1TerminatedTreatmentPulmonary Arterial Hypertension (PAH)1
1TerminatedTreatmentStroke1
1TerminatedTreatmentStroke, Ischemic1
1WithdrawnSupportive CareCholangiocarcinomas / Malignant Neoplasm of Pancreas1
1, 2CompletedOtherBMI >30 kg/m2 / Metabolic Syndromes1
1, 2CompletedTreatmentCystic Fibrosis (CF)2
1, 2CompletedTreatmentErectile Dysfunction / Pharmacodynamics / Pharmacokinetics / Smoking1
1, 2CompletedTreatmentLymphangioma1
1, 2CompletedTreatmentMenstrual Cramps1
1, 2CompletedTreatmentNontuberculous Mycobacterial Infections1
1, 2CompletedTreatmentPulmonary Hypertension (PH)1
1, 2Enrolling by InvitationTreatmentHeart Failure / Renal Dysfunction1
1, 2RecruitingBasic ScienceEndothelial Dysfunction / Insulin Resistance1
1, 2RecruitingTreatmentInfertility, Female1
1, 2TerminatedTreatmentMyelodysplastic Syndromes1
1, 2Unknown StatusTreatmentHepatic Encephalopathy1
1, 2WithdrawnTreatmentCMRI of Lung Perfusion / Cystic Fibrosis With Mild to Moderate Lung Disease / Lung Perfusion / Lung Vascularization1
2Active Not RecruitingTreatmentIdiopathic Pulmonary Fibrosis (IPF)1
2CompletedNot AvailableMild to Moderate Hypertension1
2CompletedBasic ScienceBenign Prostatic Hyperplasia (BPH)1
2CompletedSupportive CareInfertilities1
2CompletedSupportive CareProstate Cancer1
2CompletedTreatmentActive Digital Ulcers1
2CompletedTreatmentAlveolitis, Fibrosing / Pulmonary Fibrosis / Pulmonary Hypertension (PH)1
2CompletedTreatmentAnovulatory cycle1
2CompletedTreatmentBecker's Muscular Dystrophy (BMD)1
2CompletedTreatmentChronic Obstructive Pulmonary Disease (COPD) / Emphysema1
2CompletedTreatmentCystic Fibrosis (CF)2
2CompletedTreatmentErectile Dysfunction4
2CompletedTreatmentFemale Sexual Arousal Disorder1
2CompletedTreatmentHeart Failure1
2CompletedTreatmentHigh Blood Pressure (Hypertension)1
2CompletedTreatmentHypoactive Sexual Desire Disorder (HSDD)1
2CompletedTreatmentHypoplastic Left Heart Syndrome (HLHS) / Tricuspid Atresia1
2CompletedTreatmentNeonates and Preterm Infants1
2CompletedTreatmentPost-Concussive Syndrome / Traumatic Brain Injury (TBI)1
2CompletedTreatmentPulmonary Fibrosis / Pulmonary Hypertension (PH)1
2CompletedTreatmentPulmonary Hypertension (PH)3
2CompletedTreatmentSexual arousal disorders / Sexual Dysfunctions, Psychological1
2CompletedTreatmentSexual arousal disorders1
2CompletedTreatmentWaldenström's Macroglobulinemia (WM)1
2Not Yet RecruitingTreatmentIntrauterine Growth Restriction1
2RecruitingBasic ScienceTraumatic Brain Injury (TBI)1
2RecruitingPreventionAtherosclerosis / Rheumatoid Arthritis1
2RecruitingPreventionDiving / Immersion / Pulmonary Edemas1
2RecruitingPreventionSmall Vessel Cerebrovascular Disease1
2RecruitingSupportive CareLymphatic Diseases / Lymphatic Malformations1
2RecruitingTreatmentBladder Cancers1
2RecruitingTreatmentBrain and Nervous System / Glioblastomas / Gliomas / Malignant Gliomas / Recurrent Adult Brain Neoplasm / WHO Grade III Glioma1
2RecruitingTreatmentChronic Lung Disease of Prematurity1
2RecruitingTreatmentConcussion, Brain / Post-Concussion Syndrome / Vascular System Injuries1
2RecruitingTreatmentInfants, Premature1
2TerminatedHealth Services ResearchAge-Related Macular Degeneration (ARMD)1
2TerminatedTreatmentBecker's Muscular Dystrophy (BMD) / Duchenne's Muscular Dystrophy (DMD)1
2TerminatedTreatmentParkinson's Disease (PD)1
2TerminatedTreatmentPersistent Pulmonary Hypertension / Respiratory Failure1
2TerminatedTreatmentPortopulmonary Hypertension1
2TerminatedTreatmentPriapism / Sickle Cell Disorders1
2TerminatedTreatmentPulmonary Hypertension (PH)2
2TerminatedTreatmentPulmonary Hypertension (PH) / Sickle Cell Disorders1
2TerminatedTreatmentProphylaxis of preeclampsia1
2WithdrawnPreventionCerebral Vasospasm / Rupture of Intracranial Aneurysm / Subarachnoid Hemorrhage1
2WithdrawnPreventionCerebral Vasospasm / Subarachnoid Hemorrhage1
2WithdrawnTreatmentPersistent Pulmonary Hypertension of the Newborn1
2, 3Active Not RecruitingTreatmentHemodialysis Complication / Pulmonary Hypertension (PH)1
2, 3CompletedTreatmentDiastolic Heart Failure / Pulmonary Hypertension (PH)1
2, 3CompletedTreatmentErectile Dysfunction1
2, 3CompletedTreatmentHeart Failure1
2, 3CompletedTreatmentInfertilities1
2, 3CompletedTreatmentLung Cancer Non-Small Cell Cancer (NSCLC)1
2, 3CompletedTreatmentPulmonary Hypertension (PH) / Thalassaemic disorders1
2, 3CompletedTreatmentRaynaud's Phenomenon1
2, 3Not Yet RecruitingTreatmentPeripheral Arterial Disease (PAD)1
2, 3Not Yet RecruitingTreatmentPreterm Preeclampsia1
2, 3RecruitingSupportive CareCystic Fibrosis (CF)1
2, 3TerminatedTreatmentDiseases of Mitral Valve / Pulmonary Hypertension (PH)1
2, 3TerminatedTreatmentIdiopathic Pulmonary Fibrosis (IPF) / Pulmonary Fibrosis1
2, 3TerminatedTreatmentIntrauterine Growth Restriction (IUGR) / Intrauterine Growth Retardation1
2, 3TerminatedTreatmentIntrauterine Growth Retardation1
2, 3Unknown StatusTreatmentCardiovascular Disease (CVD) / Chronic Lung Diseases / Pulmonary Arterial Hypertension (PAH) / Pulmonary Hypertension (PH) / Tanshinone IIA Sulfonate1
2, 3Unknown StatusTreatmentIntrauterine Growth Retardation1
3Active Not RecruitingTreatmentHeart Failure / Pulmonary Hypertension (PH)1
3Active Not RecruitingTreatmentPulmonary Hypertension, Familial Persistent, of the Newborn1
3CompletedPreventionErectile Dysfunction / Prostate Cancer1
3CompletedTreatmentChronic Lung Diseases1
3CompletedTreatmentCongestive Heart Failure2
3CompletedTreatmentDiabetes Mellitus (DM)1
3CompletedTreatmentDiffuse Systemic Sclerosis / Raynaud's Phenomenon / Scleroderma, Limited / Scleroderma, Systemic1
3CompletedTreatmentEisenmenger's Syndrome1
3CompletedTreatmentEndothelial Dysfunction / Type 2 Diabetes Mellitus1
3CompletedTreatmentErectile Dysfunction3
3CompletedTreatmentHeart Failure3
3CompletedTreatmentHeart Failure, Diastolic / Pulmonary Hypertension (PH)1
3CompletedTreatmentIdiopathic Pulmonary Fibrosis (IPF)1
3CompletedTreatmentIntrauterine Growth Retardation1
3CompletedTreatmentPeripheral Obliterative Arteriopathy1
3CompletedTreatmentPulmonary Arterial Hypertension (PAH)1
3CompletedTreatmentPulmonary Arterial Hypertension, Children1
3CompletedTreatmentPulmonary Fibrosis / Pulmonary Hypertension (PH)1
3CompletedTreatmentPulmonary Hypertension (PH)4
3CompletedTreatmentScleroderma, Systemic1
3Not Yet RecruitingTreatmentPediatric Hypertension1
3Not Yet RecruitingTreatmentPeripheral Artery Disease (PAD)1
3Not Yet RecruitingTreatmentPeripheral Obliterative Arteriopathy1
3Not Yet RecruitingTreatmentPulmonary Hypertension (PH) / Single-ventricle / Univentricular heart1
3RecruitingPreventionEnd Stage Heart Failure1
3RecruitingTreatmentErectile Dysfunction / Prostate Cancer1
3RecruitingTreatmentGlaucoma1
3RecruitingTreatmentHeart Failure / Pulmonary Hypertension (PH)1
3RecruitingTreatmentIntrauterine Growth Retardation1
3RecruitingTreatmentPulmonary Hypertension (PH) / Systolic Dysfunction1
3SuspendedTreatmentHigh Blood Pressure (Hypertension)1
3TerminatedTreatmentPulmonary Arterial Hypertension (PAH)1
3TerminatedTreatmentPulmonary Arterial Hypertension (PAH) / Pulmonary Hypertension (PH)2
3TerminatedTreatmentPulmonary Hypertension (PH)1
3Unknown StatusNot AvailablePulmonary Hypertension (PH)1
3Unknown StatusTreatmentChronic Obstructive Pulmonary Disease (COPD) / Pulmonary Hypertension (PH)1
3Unknown StatusTreatmentErectile Dysfunction2
3Unknown StatusTreatmentPersistent Fetal Circulation Syndrome1
3WithdrawnNot AvailablePulmonary Hypertension (PH)1
3WithdrawnTreatmentArteriospasm coronary1
4Active Not RecruitingTreatmentErectile Dysfunction / Prostatic Neoplasms1
4Active Not RecruitingTreatmentPulmonary Arterial Hypertension (PAH)2
4Active Not RecruitingTreatmentUreteral Stones / Urolithiasis1
4CompletedNot AvailableErectile Dysfunction3
4CompletedNot AvailableHealthy Males1
4CompletedBasic ScienceEmphysema1
4CompletedDiagnosticPulmonary Arterial Hypertension (PAH) / Ventricular Dysfunction, Left1
4CompletedEducational/Counseling/TrainingBlindness1
4CompletedPreventionHigh Altitude Pulmonary Edema / Other and unspecified effects of high altitude1
4CompletedTreatmentAngina Pectoris1
4CompletedTreatmentAortic Valve Stenosis1
4CompletedTreatmentArterial Hypertension / Erectile Dysfunction1
4CompletedTreatmentChronic Obstructive Pulmonary Disease (COPD) / Pulmonary Hypertension (PH)2
4CompletedTreatmentDepression / Erectile Dysfunction1
4CompletedTreatmentDepression / Sexual Dysfunctions1
4CompletedTreatmentDiabetes Mellitus (DM) / Erectile Dysfunction / Testosterone Deficiency1
4CompletedTreatmentDiabetic Neuropathies1
4CompletedTreatmentEndometrial Preparation / Frozen Embryo Transfer1
4CompletedTreatmentEndothelial Dysfunction / Type 2 Diabetes Mellitus1
4CompletedTreatmentErectile Dysfunction20
4CompletedTreatmentErectile Dysfunction / Hemodialysis Treatment1
4CompletedTreatmentErectile Dysfunction / High Blood Pressure (Hypertension)1
4CompletedTreatmentErectile Dysfunction / Parkinsons's Disease1
4CompletedTreatmentErectile Dysfunction / Premature Ejaculation1
4CompletedTreatmentErectile Dysfunction / Spinal Cord Injuries (SCI) / Spinal Cord Trauma1
4CompletedTreatmentErectile Dysfunction / Type 2 Diabetes Mellitus1
4CompletedTreatmentFontan Circulation1
4CompletedTreatmentHeart Failure, Diastolic1
4CompletedTreatmentHeart Failure / Symptomatic left ventricular ejection fraction ≤ 35% Chronic heart failure1
4CompletedTreatmentMeconium Aspiration Syndrome / Persistent Pulmonary Hypertension of Newborn (PPHN)1
4CompletedTreatmentMenière's Disease1
4CompletedTreatmentMitral Valve Surgery / Pulmonary Hypertension (PH)1
4CompletedTreatmentPediatric Pulmonary Hypertension1
4CompletedTreatmentPulmonary Arterial Hypertension (PAH)3
4CompletedTreatmentPulmonary Arterial Hypertension (PAH) / Pulmonary Hypertension (PH)1
4CompletedTreatmentPulmonary Hypertension (PH) / Valvular Heart Disease1
4CompletedTreatmentPulmonary Hypertension Associated With Connective Tissue Disease1
4CompletedTreatmentQuality of Life1
4CompletedTreatmentSafety1
4CompletedTreatmentSchizophrenic Disorders1
4No Longer AvailableNot AvailablePulmonary Arterial Hypertension (PAH)1
4Not Yet RecruitingBasic ScienceHealthy Volunteers1
4Not Yet RecruitingTreatmentMyopathies1
4RecruitingBasic ScienceEmphysema2
4RecruitingTreatmentAssociated Pulmonary Arterial Hypertension1
4RecruitingTreatmentBMI >30 kg/m21
4RecruitingTreatmentIVF Failure1
4RecruitingTreatmentInfertilities1
4RecruitingTreatmentLife Change Events / Pulmonary Arterial Hypertension (PAH)1
4RecruitingTreatmentPulmonary Arterial Hypertension (PAH)1
4RecruitingTreatmentThalassaemic disorders1
4TerminatedTreatmentHeart Failure With Reactive Pulmonary Hypertension1
4TerminatedTreatmentHernia, Diaphragmatic / Hypoplasia, Pulmonary / Pulmonary Hypertension (PH)1
4TerminatedTreatmentProstatitis1
4TerminatedTreatmentPulmonary Arterial Hypertension (PAH)1
4Unknown StatusTreatmentCardiopulmonary Bypass1
4Unknown StatusTreatmentChronic Obstructive Pulmonary Disease (COPD) / Idiopathic Pulmonary Fibrosis (IPF)1
4Unknown StatusTreatmentErectile Dysfunction3
4Unknown StatusTreatmentHeart Failure1
4Unknown StatusTreatmentIUGR1
4Unknown StatusTreatmentMyalgic Encephalomyelitis (ME)1
4Unknown StatusTreatmentPulmonary Arterial Hypertension (PAH)1
4Unknown StatusTreatmentPulmonary Hypertension Secondary to Lung Disease and/or Hypoxia1
4Unknown StatusTreatmentRecurrent Miscarriages1
4WithdrawnTreatmentChronic Obstructive Pulmonary Disease (COPD) / Pulmonary Hypertension (PH)1
4WithdrawnTreatmentIdiopathic Pulmonary Fibrosis (IPF) / Interstitial Lung Disease (ILD) / Pulmonary Arterial Hypertension (PAH) / Pulmonary Hypertension (PH)1
4WithdrawnTreatmentSickle Cell Disorders1
Not AvailableActive Not RecruitingBasic ScienceMigraine With Aura1
Not AvailableActive Not RecruitingTreatmentErectile Dysfunction / Penile Cancer / Radical Prostatectomy1
Not AvailableCompletedNot AvailableAcute iron intoxication / Beta-Thalassemia / Hematologic Diseases / Osteoporosis / Pulmonary Hypertension (PH) / Thalassaemic disorders / Thalassemia Major (TM)1
Not AvailableCompletedNot AvailableHigh Blood Pressure (Hypertension)1
Not AvailableCompletedNot AvailableHigh Blood Pressure (Hypertension) / Multiple System Atrophy (MSA) / Progressive autonomic failure1
Not AvailableCompletedNot AvailableProstate Cancer1
Not AvailableCompletedNot AvailablePulmonary Arterial Hypertension (PAH)2
Not AvailableCompletedNot AvailablePulmonary Hypertension (PH)2
Not AvailableCompletedBasic ScienceAir Pollution / Exercise Performance / Pulmonary Artery Pressure / Pulmonary Hypertension (PH)1
Not AvailableCompletedBasic ScienceAltitude / Arterial hypoxia / Exercise / Sildenafil1
Not AvailableCompletedDiagnosticCongenital Heart Disease (CHD)1
Not AvailableCompletedDiagnosticDiffuse Parenchymal Lung Diseases / Pulmonary Hypertension (PH)1
Not AvailableCompletedDiagnosticEndometrial Thickness1
Not AvailableCompletedHealth Services ResearchBMI >30 kg/m21
Not AvailableCompletedOtherErectile Dysfunction1
Not AvailableCompletedSupportive CareErectile Dysfunction / Prostate Cancer / Stage I Prostate Cancer / Stage II Prostate Cancer1
Not AvailableCompletedSupportive CareProstate Cancer / Psychosocial Effects of Cancer and Its Treatment / Radiation Toxicity / Sexual Dysfunctions / Sexuality and Reproductive Issues1
Not AvailableCompletedTreatmentAging / Tiredness1
Not AvailableCompletedTreatmentAnovulatory cycle1
Not AvailableCompletedTreatmentComplications, Pregnancy1
Not AvailableCompletedTreatmentDuchenne's Muscular Dystrophy (DMD)1
Not AvailableCompletedTreatmentHealthy Volunteers1
Not AvailableCompletedTreatmentHigh Blood Pressure (Hypertension)1
Not AvailableCompletedTreatmentImprove Endothelial Function and Decrease Vascular Stenosis1
Not AvailableCompletedTreatmentNephrogenic Diabetes Insipidus1
Not AvailableCompletedTreatmentPulmonary Arterial Hypertension (PAH)1
Not AvailableCompletedTreatmentRecurrent Abortion1
Not AvailableCompletedTreatmentTiredness1
Not AvailableNo Longer AvailableNot AvailablePulmonary Arterial Hypertension (PAH)3
Not AvailableNot Yet RecruitingTreatmentInfertilities1
Not AvailableNot Yet RecruitingTreatmentRenal Transplant Failure1
Not AvailableRecruitingNot AvailableHigh Risk Pregnancies1
Not AvailableRecruitingNot AvailablePulmonary Arterial Hypertension (PAH)1
Not AvailableRecruitingNot AvailableTbi1
Not AvailableRecruitingTreatmentChronic Obstructive Pulmonary Disease (COPD) / Pulmonary Hypertension (PH)1
Not AvailableRecruitingTreatmentComplications, Pregnancy1
Not AvailableRecruitingTreatmentCongenital Heart Disease (CHD) / Pulmonary Arterial Hypertension (PAH)1
Not AvailableRecruitingTreatmentPreeclampsia1
Not AvailableTerminatedSupportive CareErectile Dysfunction / Erectile Dysfunction Following Radical Prostatectomy / Erectile Dysfunction Following Simple Prostatectomy / Prostate Cancer1
Not AvailableUnknown StatusBasic ScienceCongenital Heart Disease (CHD)1
Not AvailableUnknown StatusDiagnosticErectile Dysfunction1
Not AvailableUnknown StatusEducational/Counseling/TrainingErectile Dysfunction1
Not AvailableUnknown StatusTreatmentPersistent Pulmonary Hypertension of Newborn (PPHN)1
Not AvailableUnknown StatusTreatmentProstate Cancer1
Not AvailableWithdrawnOtherCardiac Allograft Vasculopathy1
Not AvailableWithdrawnTreatmentPrimary and Secondary Pulmonary Hypertension1

Pharmacoeconomics

Manufacturers
  • Pfizer inc
  • Pfizer ireland pharmaceuticals
Packagers
  • A-S Medication Solutions LLC
  • Bryant Ranch Prepack
  • Cardinal Health
  • Direct Dispensing Inc.
  • Diversified Healthcare Services Inc.
  • Gallipot
  • MSN Laboratories Ltd.
  • Murfreesboro Pharmaceutical Nursing Supply
  • Nucare Pharmaceuticals Inc.
  • PD-Rx Pharmaceuticals Inc.
  • Pfizer Inc.
  • Physicians Total Care Inc.
  • Preferred Pharmaceuticals Inc.
  • Prepackage Specialists
  • Prepak Systems Inc.
  • Rebel Distributors Corp.
  • Redpharm Drug
  • Southwood Pharmaceuticals
  • Stat Rx Usa
  • US Pharmaceutical Group
Dosage forms
FormRouteStrength
TabletOral
Injection, solutionIntravenous0.8 mg/1mL
Injection, solutionIntravenous0.8 mg/ml
Powder, for suspensionOral10 mg/ml
Powder, for suspensionOral10 mg/1mL
SolutionIntravenous0.8 mg
TabletOral20 mg
Tablet, film coatedOral20 mg
For suspensionOral10 mg/1mL
Injection, solutionIntravenous10 mg/12.5mL
TabletOral100 mg
TabletOral100.0 mg
TabletOral20 mg/1
TabletOral25.0 mg
TabletOral50.0 mg
Tablet, film coatedOral20 mg/1
TabletOral25 mg
Tablet, film coatedOral100 1/1
Tablet, film coatedOral100 mg
Tablet, film coatedOral25 mg
Tablet, film coatedOral50 mg
TabletOral50 mg
Tablet, film coatedOral100 mg/1
Tablet, film coatedOral25 mg/1
Tablet, film coatedOral50 mg/1
Tablet, orally disintegratingOral50 mg
Tablet, orally disintegratingOral100 mg
Tablet, orally disintegratingOral25 mg
Prices
Unit descriptionCostUnit
Sildenafil citrate powder24.38USD g
Viagra 50 mg tablet19.45USD tablet
Viagra 100 mg tablet19.45USD tablet
Viagra 25 mg tablet19.45USD tablet
Revatio 20 mg tablet17.5USD tablet
Revatio 10 mg/12.5 ml vial9.33USD ml
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only.
Patents
Patent NumberPediatric ExtensionApprovedExpires (estimated)
US5250534No1993-10-052012-03-27Us
CA2324324No2005-12-202020-10-26Canada
CA2044748No1998-02-032011-06-17Canada
US6469012Yes2002-10-222020-04-22Us
Additional Data Available
  • Filed On
    Filed On

    The date on which a patent was filed with the relevant government.

    Learn more

Properties

State
Solid
Experimental Properties
PropertyValueSource
melting point (°C)189-190 °CNot Available
water solubility3.5 mg/mLNot Available
logP1.9Not Available
Predicted Properties
PropertyValueSource
Water Solubility0.433 mg/mLALOGPS
logP2.35ALOGPS
logP1.65ChemAxon
logS-3ALOGPS
pKa (Strongest Acidic)7.27ChemAxon
pKa (Strongest Basic)5.97ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count8ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area109.13 Å2ChemAxon
Rotatable Bond Count6ChemAxon
Refractivity139.44 m3·mol-1ChemAxon
Polarizability51.18 Å3ChemAxon
Number of Rings4ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleYesChemAxon
Predicted ADMET features
PropertyValueProbability
Human Intestinal Absorption+1.0
Blood Brain Barrier+0.6461
Caco-2 permeable+0.7078
P-glycoprotein substrateSubstrate0.7753
P-glycoprotein inhibitor IInhibitor0.672
P-glycoprotein inhibitor IIInhibitor0.8877
Renal organic cation transporterNon-inhibitor0.648
CYP450 2C9 substrateNon-substrate0.6553
CYP450 2D6 substrateSubstrate0.8918
CYP450 3A4 substrateSubstrate0.7254
CYP450 1A2 substrateNon-inhibitor0.823
CYP450 2C9 inhibitorInhibitor0.6864
CYP450 2D6 inhibitorNon-inhibitor0.8394
CYP450 2C19 inhibitorNon-inhibitor0.8222
CYP450 3A4 inhibitorInhibitor0.849
CYP450 inhibitory promiscuityHigh CYP Inhibitory Promiscuity0.5839
Ames testNon AMES toxic0.5683
CarcinogenicityNon-carcinogens0.6658
BiodegradationNot ready biodegradable0.7641
Rat acute toxicity2.6730 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.8664
hERG inhibition (predictor II)Inhibitor0.7602
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)

Spectra

Mass Spec (NIST)
Not Available
Spectra
SpectrumSpectrum TypeSplash Key
Predicted GC-MS Spectrum - GC-MSPredicted GC-MSNot Available
Predicted MS/MS Spectrum - 10V, Positive (Annotated)Predicted LC-MS/MSsplash10-004i-0002900000-b281f59f40caaba85ac9
Predicted MS/MS Spectrum - 20V, Positive (Annotated)Predicted LC-MS/MSsplash10-004i-4436900000-0c5804e76b9d495c76d6
Predicted MS/MS Spectrum - 40V, Positive (Annotated)Predicted LC-MS/MSsplash10-0459-6292000000-5a32bfcdda2067978be9
Predicted MS/MS Spectrum - 10V, Negative (Annotated)Predicted LC-MS/MSsplash10-00di-0001900000-51b4957d0b3d25c41773
Predicted MS/MS Spectrum - 20V, Negative (Annotated)Predicted LC-MS/MSsplash10-01vk-0302900000-86c63c2fd17f7c5b7d6f
Predicted MS/MS Spectrum - 40V, Negative (Annotated)Predicted LC-MS/MSsplash10-03dj-8916100000-e941afc576d544ed32a7
LC-MS/MS Spectrum - LC-ESI-qTof , PositiveLC-MS/MSNot Available
LC-MS/MS Spectrum - LC-ESI-qTof , PositiveLC-MS/MSNot Available
MS/MS Spectrum - , positiveLC-MS/MSsplash10-0059-2494500000-e3f8387aee5a0463363c
MS/MS Spectrum - , positiveLC-MS/MSsplash10-05s0-3892000000-aa19715309275e16a6c0

Taxonomy

Description
This compound belongs to the class of organic compounds known as benzenesulfonamides. These are organic compounds containing a sulfonamide group that is S-linked to a benzene ring.
Kingdom
Organic compounds
Super Class
Benzenoids
Class
Benzene and substituted derivatives
Sub Class
Benzenesulfonamides
Direct Parent
Benzenesulfonamides
Alternative Parents
Pyrazolopyrimidines / Benzenesulfonyl compounds / Phenoxy compounds / Phenol ethers / Pyrimidones / Alkyl aryl ethers / N-methylpiperazines / Organosulfonamides / Sulfonyls / Pyrazoles
show 7 more
Substituents
Benzenesulfonamide / Pyrazolopyrimidine / Benzenesulfonyl group / Phenoxy compound / Phenol ether / Alkyl aryl ether / Pyrimidone / N-methylpiperazine / N-alkylpiperazine / Piperazine
show 25 more
Molecular Framework
Aromatic heteropolycyclic compounds
External Descriptors
sulfonamide, piperazines, pyrazolopyrimidine (CHEBI:9139)

Targets

Kind
Protein
Organism
Humans
Pharmacological action
Yes
Actions
Inhibitor
General Function
Metal ion binding
Specific Function
Plays a role in signal transduction by regulating the intracellular concentration of cyclic nucleotides. This phosphodiesterase catalyzes the specific hydrolysis of cGMP to 5'-GMP (PubMed:9714779, ...
Gene Name
PDE5A
Uniprot ID
O76074
Uniprot Name
cGMP-specific 3',5'-cyclic phosphodiesterase
Molecular Weight
99984.14 Da
References
  1. Carson CC: Long-term use of sildenafil. Expert Opin Pharmacother. 2003 Mar;4(3):397-405. [PubMed:12614192]
  2. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [PubMed:11752352]
  3. Corbin JD, Francis SH, Webb DJ: Phosphodiesterase type 5 as a pharmacologic target in erectile dysfunction. Urology. 2002 Sep;60(2 Suppl 2):4-11. [PubMed:12414329]
  4. Kruuse C, Thomsen LL, Birk S, Olesen J: Migraine can be induced by sildenafil without changes in middle cerebral artery diameter. Brain. 2003 Jan;126(Pt 1):241-7. [PubMed:12477710]
  5. Rybalkin SD, Rybalkina IG, Shimizu-Albergine M, Tang XB, Beavo JA: PDE5 is converted to an activated state upon cGMP binding to the GAF A domain. EMBO J. 2003 Feb 3;22(3):469-78. [PubMed:12554648]
  6. Wang H, Liu Y, Huai Q, Cai J, Zoraghi R, Francis SH, Corbin JD, Robinson H, Xin Z, Lin G, Ke H: Multiple conformations of phosphodiesterase-5: implications for enzyme function and drug development. J Biol Chem. 2006 Jul 28;281(30):21469-79. Epub 2006 May 30. [PubMed:16735511]
  7. Wang H, Ye M, Robinson H, Francis SH, Ke H: Conformational variations of both phosphodiesterase-5 and inhibitors provide the structural basis for the physiological effects of vardenafil and sildenafil. Mol Pharmacol. 2008 Jan;73(1):104-10. Epub 2007 Oct 24. [PubMed:17959709]
  8. Wang J, Re J, Wang Z: [Mode of action of sildenafil]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 1999 Dec;21(6):493-6. [PubMed:12567500]
  9. Zoraghi R, Francis SH, Corbin JD: Critical amino acids in phosphodiesterase-5 catalytic site that provide for high-affinity interaction with cyclic guanosine monophosphate and inhibitors. Biochemistry. 2007 Nov 27;46(47):13554-63. Epub 2007 Nov 3. [PubMed:17979301]
Kind
Protein
Organism
Humans
Pharmacological action
No
Actions
Inhibitor
General Function
Enzyme inhibitor activity
Specific Function
Participates in processes of transmission and amplification of the visual signal. cGMP-PDEs are the effector molecules in G-protein-mediated phototransduction in vertebrate rods and cones.
Gene Name
PDE6G
Uniprot ID
P18545
Uniprot Name
Retinal rod rhodopsin-sensitive cGMP 3',5'-cyclic phosphodiesterase subunit gamma
Molecular Weight
9643.09 Da
References
  1. Uckert S, Hedlund P, Andersson KE, Truss MC, Jonas U, Stief CG: Update on phosphodiesterase (PDE) isoenzymes as pharmacologic targets in urology: present and future. Eur Urol. 2006 Dec;50(6):1194-207; discussion 1207. Epub 2006 Jun 6. [PubMed:16815627]
Kind
Protein
Organism
Humans
Pharmacological action
No
Actions
Inhibitor
General Function
Enzyme inhibitor activity
Specific Function
Participates in processes of transmission and amplification of the visual signal. cGMP-PDEs are the effector molecules in G-protein-mediated phototransduction in vertebrate rods and cones.
Gene Name
PDE6H
Uniprot ID
Q13956
Uniprot Name
Retinal cone rhodopsin-sensitive cGMP 3',5'-cyclic phosphodiesterase subunit gamma
Molecular Weight
9074.36 Da
References
  1. Uckert S, Hedlund P, Andersson KE, Truss MC, Jonas U, Stief CG: Update on phosphodiesterase (PDE) isoenzymes as pharmacologic targets in urology: present and future. Eur Urol. 2006 Dec;50(6):1194-207; discussion 1207. Epub 2006 Jun 6. [PubMed:16815627]

Enzymes

Kind
Protein
Organism
Humans
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
  1. Ku HY, Ahn HJ, Seo KA, Kim H, Oh M, Bae SK, Shin JG, Shon JH, Liu KH: The contributions of cytochromes P450 3A4 and 3A5 to the metabolism of the phosphodiesterase type 5 inhibitors sildenafil, udenafil, and vardenafil. Drug Metab Dispos. 2008 Jun;36(6):986-90. doi: 10.1124/dmd.107.020099. Epub 2008 Feb 28. [PubMed:18308836]
  2. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
  3. Hyland R, Roe EG, Jones BC, Smith DA: Identification of the cytochrome P450 enzymes involved in the N-demethylation of sildenafil. Br J Clin Pharmacol. 2001 Mar;51(3):239-48. doi: 10.1046/j.1365-2125.2001.00318.x. [PubMed:11298070]
  4. Rendic S: Summary of information on human CYP enzymes: human P450 metabolism data. Drug Metab Rev. 2002 Feb-May;34(1-2):83-448. [PubMed:11996015]
  5. Flockhart Table of Drug Interactions [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Oxygen binding
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
CYP3A5
Uniprot ID
P20815
Uniprot Name
Cytochrome P450 3A5
Molecular Weight
57108.065 Da
References
  1. Ku HY, Ahn HJ, Seo KA, Kim H, Oh M, Bae SK, Shin JG, Shon JH, Liu KH: The contributions of cytochromes P450 3A4 and 3A5 to the metabolism of the phosphodiesterase type 5 inhibitors sildenafil, udenafil, and vardenafil. Drug Metab Dispos. 2008 Jun;36(6):986-90. doi: 10.1124/dmd.107.020099. Epub 2008 Feb 28. [PubMed:18308836]
  2. Flockhart Table of Drug Interactions [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Oxygen binding
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
CYP3A7
Uniprot ID
P24462
Uniprot Name
Cytochrome P450 3A7
Molecular Weight
57525.03 Da
References
  1. Flockhart Table of Drug Interactions [Link]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
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
CYP2C9
Uniprot ID
P11712
Uniprot Name
Cytochrome P450 2C9
Molecular Weight
55627.365 Da
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
  2. Hyland R, Roe EG, Jones BC, Smith DA: Identification of the cytochrome P450 enzymes involved in the N-demethylation of sildenafil. Br J Clin Pharmacol. 2001 Mar;51(3):239-48. doi: 10.1046/j.1365-2125.2001.00318.x. [PubMed:11298070]
  3. Sildenafil FDA label [File]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
Inhibitor
General Function
Steroid hydroxylase activity
Specific Function
Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and im...
Gene Name
CYP2C19
Uniprot ID
P33261
Uniprot Name
Cytochrome P450 2C19
Molecular Weight
55930.545 Da
References
  1. Warrington JS, Shader RI, von Moltke LL, Greenblatt DJ: In vitro biotransformation of sildenafil (Viagra): identification of human cytochromes and potential drug interactions. Drug Metab Dispos. 2000 Apr;28(4):392-7. [PubMed:10725306]
  2. Hyland R, Roe EG, Jones BC, Smith DA: Identification of the cytochrome P450 enzymes involved in the N-demethylation of sildenafil. Br J Clin Pharmacol. 2001 Mar;51(3):239-48. doi: 10.1046/j.1365-2125.2001.00318.x. [PubMed:11298070]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
General Function
Steroid hydroxylase activity
Specific Function
Responsible for the metabolism of many drugs and environmental chemicals that it oxidizes. It is involved in the metabolism of drugs such as antiarrhythmics, adrenoceptor antagonists, and tricyclic...
Gene Name
CYP2D6
Uniprot ID
P10635
Uniprot Name
Cytochrome P450 2D6
Molecular Weight
55768.94 Da
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [PubMed:19515014]
  2. Warrington JS, Shader RI, von Moltke LL, Greenblatt DJ: In vitro biotransformation of sildenafil (Viagra): identification of human cytochromes and potential drug interactions. Drug Metab Dispos. 2000 Apr;28(4):392-7. [PubMed:10725306]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
Inhibitor
General Function
Steroid hydroxylase activity
Specific Function
Metabolizes several precarcinogens, drugs, and solvents to reactive metabolites. Inactivates a number of drugs and xenobiotics and also bioactivates many xenobiotic substrates to their hepatotoxic ...
Gene Name
CYP2E1
Uniprot ID
P05181
Uniprot Name
Cytochrome P450 2E1
Molecular Weight
56848.42 Da
References
  1. Sheweita SA, Wally M, Hassan M: Erectile Dysfunction Drugs Changed the Protein Expressions and Activities of Drug-Metabolising Enzymes in the Liver of Male Rats. Oxid Med Cell Longev. 2016;2016:4970906. doi: 10.1155/2016/4970906. Epub 2016 Oct 9. [PubMed:27800121]
  2. List of drugs that may have potential CYP2E1 interactions [File]

Transporters

Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Inhibitor
General Function
Atpase activity, coupled to transmembrane movement of substances
Specific Function
May be an organic anion pump relevant to cellular detoxification.
Gene Name
ABCC4
Uniprot ID
O15439
Uniprot Name
Multidrug resistance-associated protein 4
Molecular Weight
149525.33 Da
References
  1. Chen ZS, Lee K, Walther S, Raftogianis RB, Kuwano M, Zeng H, Kruh GD: Analysis of methotrexate and folate transport by multidrug resistance protein 4 (ABCC4): MRP4 is a component of the methotrexate efflux system. Cancer Res. 2002 Jun 1;62(11):3144-50. [PubMed:12036927]
  2. Reid G, Wielinga P, Zelcer N, De Haas M, Van Deemter L, Wijnholds J, Balzarini J, Borst P: Characterization of the transport of nucleoside analog drugs by the human multidrug resistance proteins MRP4 and MRP5. Mol Pharmacol. 2003 May;63(5):1094-103. [PubMed:12695538]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Inhibitor
General Function
Organic anion transmembrane transporter activity
Specific Function
Acts as a multispecific organic anion pump which can transport nucleotide analogs.
Gene Name
ABCC5
Uniprot ID
O15440
Uniprot Name
Multidrug resistance-associated protein 5
Molecular Weight
160658.8 Da
References
  1. Jedlitschky G, Burchell B, Keppler D: The multidrug resistance protein 5 functions as an ATP-dependent export pump for cyclic nucleotides. J Biol Chem. 2000 Sep 29;275(39):30069-74. [PubMed:10893247]
  2. Reid G, Wielinga P, Zelcer N, De Haas M, Van Deemter L, Wijnholds J, Balzarini J, Borst P: Characterization of the transport of nucleoside analog drugs by the human multidrug resistance proteins MRP4 and MRP5. Mol Pharmacol. 2003 May;63(5):1094-103. [PubMed:12695538]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Inhibitor
General Function
Atpase activity, coupled to transmembrane movement of substances
Specific Function
ATP-dependent transporter probably involved in cellular detoxification through lipophilic anion extrusion.
Gene Name
ABCC10
Uniprot ID
Q5T3U5
Uniprot Name
Multidrug resistance-associated protein 7
Molecular Weight
161627.375 Da
References
  1. Chen ZS, Hopper-Borge E, Belinsky MG, Shchaveleva I, Kotova E, Kruh GD: Characterization of the transport properties of human multidrug resistance protein 7 (MRP7, ABCC10). Mol Pharmacol. 2003 Feb;63(2):351-8. [PubMed:12527806]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Inhibitor
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
  1. Kalliokoski A, Niemi M: Impact of OATP transporters on pharmacokinetics. Br J Pharmacol. 2009 Oct;158(3):693-705. doi: 10.1111/j.1476-5381.2009.00430.x. Epub 2009 Sep 25. [PubMed:19785645]
Kind
Protein
Organism
Humans
Pharmacological action
Unknown
Actions
Substrate
Inhibitor
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
  1. Shi Z, Tiwari AK, Shukla S, Robey RW, Singh S, Kim IW, Bates SE, Peng X, Abraham I, Ambudkar SV, Talele TT, Fu LW, Chen ZS: Sildenafil reverses ABCB1- and ABCG2-mediated chemotherapeutic drug resistance. Cancer Res. 2011 Apr 15;71(8):3029-41. doi: 10.1158/0008-5472.CAN-10-3820. Epub 2011 Mar 14. [PubMed:21402712]
  2. Higashi H, Watanabe N, Tamura R, Taguchi M: In Vitro P-Glycoprotein-Mediated Transport of Tadalafil: A Comparison with Sildenafil. Biol Pharm Bull. 2017;40(8):1314-1319. doi: 10.1248/bpb.b17-00278. [PubMed:28769012]

Drug created on June 13, 2005 07:24 / Updated on November 16, 2019 10:19