Phosphodiesterase type 5 (PDE5) inhibitor
Avanafil and grapefruit: a real interaction?
Grapefruit is famous as the juice that interacts with medications, and the warning is real for a number of drugs. Whether it matters specifically for Avanafil (Avanafil) at 50mg, 100mg, 200mg depends on whether the active ingredient Avanafil is metabolised by CYP3A4 in the gut wall and how much that pathway contributes to first-pass metabolism.
The CYP3A4 mechanism
Grapefruit (and its juice) inhibits CYP3A4 enzymes in the gut wall, increasing the absorbed dose of medications metabolised by that enzyme. For drugs in the Phosphodiesterase type 5 (PDE5) inhibitor class that go through CYP3A4 first-pass metabolism, regular grapefruit consumption can raise plasma levels of Avanafil by a clinically meaningful margin and amplify side effects.
What to do with Avanafil
According to the prescribing information for Avanafil, if grapefruit is flagged as an interaction, the safest practice is to avoid grapefruit entirely or to discuss timing with the prescriber. Avanafil selectively inhibits phosphodiesterase type 5 (PDE5) in the corpus cavernosum, increasing cGMP and enhancing nitric-oxide-mediated vasodilation in response to sexual stimulation. A small occasional serving may be tolerable; daily large servings around the time of Avanafil dosing are not recommended at 50mg, 100mg, 200mg.
Frequently asked questions
Can I eat grapefruit while on Avanafil? ▾
For some Phosphodiesterase type 5 (PDE5) inhibitor medications, grapefruit is best avoided or limited because of CYP3A4 inhibition. Whether Avanafil specifically is affected depends on Avanafil; the prescribing information lists this. When in doubt, ask the pharmacist or check the patient leaflet.
How much grapefruit is too much with Avanafil? ▾
For drugs where the interaction matters, even modest daily grapefruit intake (one whole grapefruit or one large glass of juice) can shift drug levels noticeably. For Avanafil at 50mg, 100mg, 200mg, individual tolerance varies; the cautious choice is to avoid grapefruit if any interaction is mentioned.
Products containing Avanafil
More on Avanafil
- With alcoholAvanafil and alcohol — is it safe to drink?
- With foodShould Avanafil be taken with food?
- Side effectsAvanafil side effects: common, rare and warning signs
- Dosage guideAvanafil dosage guide: how much to take and when
- OnsetHow fast does Avanafil start working?
- DurationHow long does Avanafil last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.