Description

Simple

A medication used to treat the inability to get or keep an erection.

Clinical

A phosphodiesterase inhibitor used for the treatment of erectile dysfunction.

Overview

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 consequent... Read more

Pharmacology

Indication

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

(1) the treatment of erectile dysfunction [ Read more

Pharmacodynamic

In vitro studies have shown that sildenafil is selective for phosphodiesterase-5 (PDE5) [11, 12, Read more

Mechanism of action

Sildenafil is an oral therapy for erectile dysfunction [ Read more

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, Read more

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, Read more

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, Read more

Clearance

The total body clearance documented for sildenafil is 41 L/h [11, 12, Read more

Half life

The terminal phase half-life observed for sildenafil is approximately 3 to 5 hours [11, 12, Read more

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) [ Read more

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, Read more

Adverse Effects

Effect Regions Age Groups Incidences Evidence Type
Headache US
  • adult
  • Kind: experimental
    • Percent: 16-46%
  • Kind: placebo
    • Percent: 4-39%
  • Clinical Trial
    Dyspepsia US
    • adult
  • Kind: experimental
    • Percent: 7-17%
  • Kind: placebo
    • Percent: 2-7%
  • Clinical Trial
    Increased sensitivity to light US
    • adult
  • Kind: experimental
    • Percent: 3-11%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Color tinge to vision US
    • adult
  • Kind: experimental
    • Percent: 3-11%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Blurred vision US
    • adult
  • Kind: experimental
    • Percent: 3-11%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Flushing US
    • adult
  • Kind: experimental
    • Percent: 10%
  • Kind: placebo
    • Percent: 1-4%
  • Clinical Trial
    Diarrhea US
    • adult
  • Kind: experimental
    • Percent: 3-9%
  • Kind: placebo
    • Percent: 1-6%
  • Clinical Trial
    Epistaxis US
    • adult
  • Kind: experimental
    • Percent: 9%
  • Kind: placebo
    • Percent: 1%
  • Clinical Trial
    Myalgia US
    • adult
  • Kind: experimental
    • Percent: 7%
  • Kind: placebo
    • Percent: 4%
  • Clinical Trial
    Exacerbation of dyspnea US
    • adult
  • Kind: experimental
    • Percent: 7%
  • Kind: placebo
    • Percent: 3%
  • Clinical Trial
    Insomnia US
    • adult
  • Kind: experimental
    • Percent: 7%
  • Kind: placebo
    • Percent: 1%
  • Clinical Trial
    Erythema US
    • adult
  • Kind: experimental
    • Percent: 6%
  • Kind: placebo
    • Percent: 1%
  • Clinical Trial
    Pyrexia US
    • adult
  • Kind: experimental
    • Percent: 6%
  • Kind: placebo
    • Percent: 3%
  • Clinical Trial
    Rhinitis US
    • adult
  • Kind: experimental
    • Percent: 4%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Nasal Congestion US
    • adult
  • Kind: experimental
    • Percent: 4%
  • Kind: placebo
    • Percent: 2%
  • Clinical Trial
    Urinary Tract Infection US
    • adult
  • Kind: experimental
    • Percent: 3%
  • Kind: placebo
    • Percent: 2%
  • Clinical Trial
    Paresthesia US
    • adult
  • Kind: experimental
    • Percent: 3%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Sinusitis US
    • adult
  • Kind: experimental
    • Percent: 3%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Gastritis US
    • adult
  • Kind: experimental
    • Percent: 3%
  • Kind: placebo
    • Percent: 0%
  • Clinical Trial
    Anorgasmia US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Urinary Incontinence US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Abnormal ejaculation US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Genital edema US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Sudden decrease or loss of hearing US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Contact Dermatitis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Exfoliative dermatitis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Conjunctivitis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Photophobia US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Mydriasis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Herpes Simplex US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Pruritis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Urticaria US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Skin Ulcer US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Sweating US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Nocturia US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Cystitis US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Dry Eyes US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Breast enlargement US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Urinary Frequency US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Eye Pain US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Tinnitus US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Cataract US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Eye hemorrhage US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Ear pain US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Tremor US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Vertigo US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Depression US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Insomnia US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Somnolence US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial
    Ataxia US
    • adult
  • Kind: experimental
    • Percent: <2%
  • Clinical Trial

    Contraindications

    • Sex Group: all
    • Regions: US
    • Patient Conditions:
        • Name: Blood pressure < 90/50 mmHg at therapy initiation Severe hypotension
        • Drugbank Id: DBCOND0118168
        • Combination Of:
          • Additional Characteristics:
            • blood pressure < 90/50 mmHg at therapy initiation
          • Included Conditions:
              • Name: Severe hypotension
              • Drugbank Id: DBCOND0118169
    • Sex Group: all
    • Regions: US
    • Patient Conditions:
        • Name: Recent Myocardial Infarction
        • Drugbank Id: DBCOND0043731
        • Name: Recent Stroke
        • Drugbank Id: DBCOND0049526
    • Sex Group: all
    • Regions: US
    • Patient Conditions:
        • Name: Severe Hepatic Impairment
        • Drugbank Id: DBCOND0070791
        • Modification Of:
          • Base:
            • Name: Heptic Impairment
            • Drugbank Id: DBCOND0072269
          • Severity:
            • Includes:
              • severe
    • Sex Group: male
    • Regions: US
    • Above Age:
      • Amount: 18
      • Unit: year
    • Patient Conditions:
        • Name: Men for whom sexual activity is inadvisable
        • Drugbank Id: DBCOND0107999
    • Sex Group: all
    • Regions: US
    • Patient Conditions:
        • Name: Non-Arteritic Anterior Ischemic Optic Neuropathy
        • Drugbank Id: DBCOND0031403
    • Sex Group: all
    • Regions: US
    • With Categories:
        • Name: Cytochrome P-450 CYP3A4 Inhibitors (strong)
        • Drugbank Id: DBCAT002647
    • Sex Group: all
    • Regions: US
    • With Categories:
        • Name: Guanylate Cyclase Stimulators
        • Drugbank Id: DBCAT004472
    • Sex Group: all
    • Regions: US
    • With Categories:
        • Name: Nitric Oxide Donors
        • Drugbank Id: DBCAT000756
        • Mesh Id: D020030

    Food Interactions

    Take with or without food. If taken with a high-fat meal the medicine may take a little longer to start working.