Avanafil: what it treats, how to take it, side effects
Last updated September 3, 2026.
Avanafil (brand name Stendra) is a prescription PDE5 inhibitor for erectile dysfunction, and it is the fastest-acting one on the market. It can work as early as about 15 minutes after a dose, where older drugs in the class ask for an hour.
What does it treat?
It treats erectile dysfunction in adult men. Like the rest of its class, it improves the blood-flow response to sexual stimulation rather than creating an erection on its own, and it treats the symptom, not the cause. It does not increase desire and does not protect against sexually transmitted infections.
How do you take it?
The usual starting dose is 100 mg taken by mouth as early as about 15 minutes before sexual activity. Your doctor may raise it to 200 mg (still about 15 minutes before) or lower it to 50 mg (about 30 minutes before). Take it with or without food, and never more than once in 24 hours. The lowest dose that works is the right dose. Because it is taken as needed, there is no missed-dose problem; there is also no benefit to taking it daily.
Side effects to know
- Common: headache, flushing, nasal congestion, back pain, and cold-like symptoms.
- Serious: dangerous blood-pressure drops with nitrates or riociguat, erections lasting over 4 hours, sudden vision or hearing loss, and additive dizziness or fainting with alcohol or blood-pressure medicines, including alpha-blockers.
Who should not take it?
Do not combine avanafil with nitrates in any form, riociguat, or recreational "poppers." Strong CYP3A4 inhibitors are off the table, and moderate ones cap the dose. Use caution with heart disease, recent heart attack or stroke, very low or uncontrolled high blood pressure, severe liver or kidney disease, and inherited retinal conditions. Do not stack it with other ED drugs. It is not for women or children.
When is it an emergency?
Call 911 for chest pain after taking it (and tell responders what you took), an erection lasting more than 4 hours, sudden vision or hearing loss, or fainting that does not resolve on lying down. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
What a Pymander AI doctor consult looks like
Illustrative example, not a real member's messages.
Common questions
How fast does avanafil actually work?
The label allows dosing as early as about 15 minutes before sexual activity for the 100 mg and 200 mg doses, making it the fastest PDE5 inhibitor. The 50 mg dose is taken about 30 minutes before. Individual response varies, and sexual stimulation is still required.
Is avanafil better than Viagra or Cialis?
Different strengths. Avanafil wins on speed. Sildenafil is the cheap, familiar workhorse. Tadalafil wins on duration, up to 36 hours. None is universally better; the right pick depends on whether spontaneity, duration, cost, or side effects matter most to you.
Can I take avanafil every day?
It is designed for as-needed use, with a hard cap of once in 24 hours. If you want coverage every day without timing a dose, that is the case for daily low-dose tadalafil instead, and worth discussing with your prescriber.
Can I drink alcohol with avanafil?
Carefully. Both lower blood pressure, and the label warns that combining them adds up: more dizziness, faster heart rate, worse orthostatic drops. A drink or two is different from an evening of drinking, which undermines both safety and performance.
Why did my doctor start me at 100 mg?
Because 100 mg is the standard starting dose in the label, balancing speed and tolerability. It can go up to 200 mg if it under-delivers or down to 50 mg if side effects bother you. The goal is the lowest dose that reliably works.
Does food affect avanafil?
It can be taken with or without food, and a normal meal does not meaningfully change it. A very high-fat meal can slow absorption a bit, so if timing is everything that night, a lighter dinner helps.