Avanafil

Avanafil is a prescription medication used to treat erectile dysfunction in adult men. It belongs to the class of phosphodiesterase type 5 (PDE5) inhibitors, which facilitate an erection by increasing blood flow to the penis in response to sexual stimulation.

Mechanism and pharmacokinetics: Avanafil inhibits the PDE5 enzyme, enhancing nitric oxide–mediated vasodilation and increasing levels of cyclic GMP in penile tissue. The result is improved erectile response. The drug is rapidly absorbed and typically begins to work within 15 to 30 minutes after dosing. It can be taken with or without food; high‑fat meals do not significantly delay absorption. The effects last several hours, with duration varying among individuals.

Dosing and administration: Avanafil is taken as needed, with no more than one dose per day. The usual starting dose is 100 mg, which may be adjusted to 50 mg or 200 mg based on efficacy and tolerability, up to a maximum of 200 mg.

Contraindications and interactions: Avanafil should not be used with nitrates or nitric oxide donors due to the risk of serious hypotension. Caution is advised when used with alpha‑blockers or strong CYP3A4 inhibitors, and it should be used with care in patients with significant cardiovascular disease. Routine use in women or children is not indicated.

Adverse effects and availability: Common side effects include headache, flushing, nasal congestion, back pain, dizziness, and upset stomach. Rare but serious effects can include fainting, priapism, or sudden vision or hearing loss. Marketed brands include Stendra in the United States and Spedra in other regions.