Sildenafil

Overview of Sildenafil

Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor used primarily to manage erectile dysfunction (ED) and pulmonary arterial hypertension (PAH). By inhibiting PDE5, it increases levels of cyclic guanosine monophosphate (cGMP), which relaxes smooth muscle and enhances blood flow to specific areas. In ED, this facilitates penile erection in response to sexual stimulation. In PAH, it dilates pulmonary vessels, reducing pulmonary arterial pressure and improving exercise tolerance. Sildenafil is clinically significant as a first-line oral therapy for ED and a key treatment option for PAH, demonstrating proven efficacy and safety profiles when used under medical supervision.

Conditions & Treatment Scope

Sildenafil is indicated for:

• Erectile Dysfunction: The inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Sildenafil helps restore erectile function but requires sexual stimulation to be effective. It is not an aphrodisiac and does not increase sexual desire.

• Pulmonary Arterial Hypertension (PAH): A condition characterized by high blood pressure in the arteries of the lungs. Sildenafil improves exercise capacity and delays clinical worsening in patients with PAH.

Note: Sildenafil does not protect against sexually transmitted infections and is not approved for use in women or children (except for PAH in pediatric populations under specialist guidance).

Important Safety & Precautions

• Contraindications: Do not use with nitrates (e.g., nitroglycerin) or nitric oxide donors due to risk of severe hypotension. Avoid in patients with severe cardiovascular disorders (recent myocardial infarction, stroke, uncontrolled arrhythmia, severe heart failure, unstable angina), severe hepatic impairment, or history of non-arteritic anterior ischemic optic neuropathy (NAION).

• Common Side Effects: Headache, flushing, dyspepsia, nasal congestion, dizziness, visual disturbances (color tinge, increased sensitivity to light). These are usually transient.

• Serious Side Effects: Seek immediate medical attention for erections lasting more than 4 hours (priapism), sudden vision loss, or sudden hearing loss. Reports of NAION, an eye condition, require urgent evaluation.

• Drug Interactions: Potent CYP3A4 inhibitors (ritonavir, ketoconazole, itraconazole) increase sildenafil levels. Alpha-blockers may cause symptomatic hypotension; sildenafil should be initiated at the lowest dose if used concomitantly.

• General Precautions: Use with caution in patients with anatomical penile deformities, bleeding disorders, active peptic ulcer, or conditions predisposing to priapism. Avoid excessive alcohol as it may impair erectile function. Grapefruit juice can increase sildenafil concentrations.

• Medical Oversight: Treatment must be initiated and monitored by a healthcare professional after a thorough cardiovascular and sexual health assessment. Do not self-medicate or combine with other ED treatments.

Medical Disclaimer: The content provided here is for informational and educational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any treatment.