Avanafil

Key facts

• Avanafil (the ingredient in Stendra and Spedra) is a PDE5 inhibitor. It relaxes blood vessels so more blood reaches the penis during arousal, and it only works with sexual stimulation.
• It acts faster than other PDE5 inhibitors, working in as little as 15 to 30 minutes; the effect lasts around 6 hours. Food has little effect on how well it works.
• Never take avanafil with nitrate heart medicines (glyceryl trinitrate, isosorbide) or the pulmonary-hypertension drug riociguat. Together they can drop your blood pressure to dangerous levels.
• Seek urgent care for an erection lasting more than 4 hours, or sudden loss of vision or hearing.

What avanafil treats

Avanafil treats erectile dysfunction, the inability to get or keep an erection firm enough for sex. It has no other approved medical use. It is not a treatment for angina, low sexual desire, or premature ejaculation.

How avanafil works

An erection depends on a signal molecule called cyclic GMP relaxing the blood vessels in the penis so they fill with blood. An enzyme, PDE5, breaks that molecule down. Avanafil blocks PDE5 with high selectivity, so cyclic GMP lasts longer and the vessels stay relaxed once arousal begins. Its faster absorption is why it can act sooner than older PDE5 inhibitors.

Before you take it

• Do not use avanafil if you take any nitrate medicine or riociguat, or if a doctor has told you sex is too risky for your heart.
• Tell your prescriber about alpha-blockers, other blood-pressure medicines, recent heart attack or stroke, very low or uncontrolled high blood pressure, and severe liver or kidney disease. These may change your dose or rule the drug out.
• An erection lasting over 4 hours (priapism) can permanently damage the penis. Men with sickle cell disease, myeloma or leukaemia carry a higher risk.
• Buy only from a licensed pharmacy. Avanafil is widely counterfeited, and fakes with wrong doses or contaminants are a documented cause of harm.

Side effects

Common effects fade as the dose wears off: headache, facial flushing, a blocked or runny nose, back pain, and mild indigestion.

Stop and seek urgent medical care for any of these:

• An erection lasting more than 4 hours.
• Sudden loss or dimming of vision in one or both eyes.
• Sudden hearing loss, sometimes with ringing or dizziness.
• Chest pain, a fast or irregular heartbeat, or fainting.

Safety essentials

• The nitrate rule is absolute: no avanafil within 12 hours of any nitrate, and no nitrate given for chest pain while avanafil is in your system. If you get chest pain during sex, tell emergency staff you have taken it.
• Because avanafil acts quickly, do not take a second dose if the first has not worked; wait until your prescriber reviews your dose.
• Do not take more than one dose in 24 hours, and do not combine it with other erectile-dysfunction treatments.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.