What is the use of Sildenafil (Viagra)?

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From the Guidelines

Sildenafil is recommended as a first-line treatment for erectile dysfunction, with a typical dose of 50mg taken approximately one hour before sexual activity, due to its efficacy in improving erectile function and successful intercourse attempts, as supported by high-quality evidence 1.

Key Points

  • Sildenafil works by inhibiting phosphodiesterase type 5 (PDE5), increasing blood flow to the penis during sexual stimulation.
  • The medication should not be combined with nitrates, such as nitroglycerin, to avoid a dangerous drop in blood pressure.
  • Common side effects include headache, flushing, indigestion, nasal congestion, and visual disturbances.
  • Sildenafil typically begins working within 30-60 minutes, with effects lasting about 4-5 hours.
  • Patients with cardiovascular disease, liver or kidney problems, or certain eye conditions should use sildenafil with caution and only after consulting their healthcare provider.

Dosage and Administration

  • The typical dose of sildenafil for erectile dysfunction is 50mg, taken approximately one hour before sexual activity.
  • The dose can range from 25-100mg, depending on effectiveness and tolerability.
  • Sildenafil should not be taken more than once daily.

Efficacy and Safety

  • High-quality evidence supports the efficacy of sildenafil in improving erectile function and successful intercourse attempts 1.
  • Sildenafil has been shown to be more effective than non-PDE5 inhibitor treatments, such as sublingual apomorphine and psychotherapy, in improving erectile function and frequency of penile penetration or erection maintenance 1.
  • The safety profile of sildenafil is generally well-tolerated, with common side effects being mild to moderate in severity.

From the FDA Drug Label

Sildenafil tablets are indicated for the treatment of pulmonary arterial hypertension (WHO Group I) in adults to improve exercise ability and delay clinical worsening. The efficacy of sildenafil tablets in the treatment of pulmonary arterial hypertension (PAH) has not been adequately evaluated in patients taking bosentan. Sildenafil tablets are a prescription medicine used in adults to treat pulmonary arterial hypertension (PAH). It is not known if sildenafil tablets are effective for the treatment of PAH in people who are also taking a medicine called bosentan (Tracleer®)

The main use of sildenafil is for the treatment of pulmonary arterial hypertension (PAH) in adults to improve exercise ability and delay clinical worsening.

  • The efficacy of sildenafil in patients taking bosentan has not been adequately evaluated.
  • Sildenafil is not for use in children.
  • Contraindications include taking nitrate medicines and being allergic to sildenafil.
  • Patients should be advised to seek immediate medical attention for a sudden loss of vision or hearing while taking sildenafil tablets 2 2

From the Research

Sildenafil Overview

  • Sildenafil is a phosphodiesterase type 5 inhibitor used to treat erectile dysfunction (ED) and pulmonary arterial hypertension (PAH) 3, 4, 5, 6, 7
  • It works by increasing blood flow to the penis and relaxing blood vessels in the lungs 4, 7

Efficacy and Safety

  • Sildenafil has been shown to be effective in improving erection quality, treatment satisfaction, and reducing anxiety in men with ED 3, 5, 6
  • It is well-tolerated and has a favorable safety profile, with common adverse events including headache and flushing 3, 6
  • Sildenafil is effective in men of all ages, including those over 75 years old 6

Clinical Uses

  • Sildenafil is approved for the treatment of ED and PAH 4, 7
  • It has also been investigated for use in other conditions, including idiopathic pulmonary hypertension and endothelial dysfunction 4, 5
  • Combination therapy with other medications, such as prostacyclin analogs and endothelin receptor antagonists, may be helpful in the management of PAH 7

Dosage and Administration

  • The recommended starting dose for ED is 50 mg, taken 1 hour before sexual activity, with subsequent adjustment to 100 or 25 mg based on efficacy and safety 3, 6
  • For PAH, the approved dose is 20 mg three times daily 4, 7

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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