Products
Avanafil is commercially available in tablet form (Spedra, some countries: Stendra). It was approved in the US in April 2012, in the EU in 2013, and in many countries in 2016.
Structure and properties
Avanafil (C23H26ClN7O3, Mr = 483.95 g/mol) is a pyrimidine derivative. It exists as a white crystalline powder that is practically insoluble in water.
Effects
Avanafil (ATC G04BE) has vasodilator and antihypertensive properties. It causes smooth muscle relaxation in the corpus cavernosum and an increase in blood flow to the penis during sexual stimulation. The effects are due to inhibition of cGMP-specific phosphodiesterase type 5 (PDE-5), resulting in an increase in cGMP. Avanafil has a rapid onset of action and a medium-long half-life of about 5 hours. Unlike other phosphodiesterase-5 inhibitors, it appears to be somewhat more selective for PDE5.
Indications
For the treatment of erectile dysfunction in adult men.
Dosage
As directed in the package insert. Tablets are taken as needed about 30 minutes before sexual activity with or without food. Taking with a meal may delay onset of action.
Contraindications
For complete information on precautions and interactions, see the drug label.
Interactions
Avanafil is metabolized primarily by CYP3A4 and to a lesser extent by CYP2C9. Corresponding drug-drug interactions with inhibitors and inducers are possible. Avanafil should not be co-administered with nitrates, NO donors, or amyl nitrite. Caution is also advised when combining with alpha blockers, antihypertensives, or alcohol. Alcohol may increase adverse effects.
Adverse effects
The most common possible adverse effects include headache, feeling hot, and nasal congestion.
