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Sildenafil for Erectile Dysfunction

• PDE5 inhibitors: basic pharmacology, side effects, contraindications
• PDE5 inhibitors: Sildenafil
• PDE5 inhibitors: Tadalafil
• PDE5 inhibitors: Vardenafil

Review Literature: (Hatzimouratidis and Hatzichristou, 2007).

Basic pharmacology, side effects, drug interactions and contraindications of sildenafil please see section PDE5 inhibitors.

Indications for Sildenafil

Sildenafil is used for the medical treatment of erectile dysfunction.

Pharmacokinetics of Sildenafil

• Fast Absorption of sildenafil after oral administration: maximum effective concentrations 30–120 min after oral ingestion of sildenafil on an empty stomach. If sildenafil is taken with food, the maximum effective concentration is delayed and decreased.
• Degradation of sildenafil by hepatic cytochrome P450 (CYP3A4 and 2C9). Half-life 3–5 h. Excretion to 80% via the faeces.

Dosage of Sildenafil

In healthy men, the recommended starting dosage is 50 mg sildenafil. Depending on the effects and side effects, the dosage may then change to 25 mg or 100 mg sildenafil. In men with liver impairment, severe chronic kidney disease, cardiac risk factors, in older men, with an antihypertensive medication or with cytochrome p450 inhibitors, the recommended starting dosage is 25 mg sildenafil.

References

  Deutsche Version: Sildenafil