Drug interactions
Avanafil + Zafirlukast
Severity: Minor
Avanafil and Zafirlukast: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Avanafil is a sensitive CYP3A4 substrate, and inhibitors of this enzyme can increase its exposure and the risk of hypotension, headache and flushing. Zafirlukast is only a weak CYP3A4 inhibitor, so the effect is likely modest.
What this interaction means in plain words
Avanafil and Zafirlukast have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Avanafil belongs to Genitourinary; Zafirlukast belongs to Respiratory.
Why it happens
Zafirlukast weakly inhibits CYP3A4, reducing avanafil clearance.
What to do
Start with the usual avanafil dose and monitor for hypotension and other adverse effects. Reassess if symptoms develop.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Zafirlukast
- Pimozide + Zafirlukast Contraindicated
- Lomitapide + Zafirlukast Major
- Nilotinib + Zafirlukast Major
- Warfarin + Zafirlukast Major
- Apalutamide + Zafirlukast Moderate
- Carbamazepine + Zafirlukast Moderate
Other interactions of Avanafil
- Amyl nitrite + Avanafil Contraindicated
- Atazanavir + Avanafil Contraindicated
- Avanafil + Clarithromycin Contraindicated
- Avanafil + Conivaptan Contraindicated
- Avanafil + Darunavir Contraindicated
- Avanafil + Fosamprenavir Contraindicated
Frequently asked questions
Can I take Avanafil with Zafirlukast?
MediHelp rates the interaction as minor. Avanafil and Zafirlukast have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Avanafil is a sensitive CYP3A4 substrate, and inhibitors of this enzyme can increase its exposure and the risk of hypotension, headache and flushing. Zafirlukast is only a weak CYP3A4 inhibitor, so the effect is likely modest.
How serious is the interaction between Avanafil and Zafirlukast?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Start with the usual avanafil dose and monitor for hypotension and other adverse effects. Reassess if symptoms develop.
What other medicines interact with Zafirlukast?
MediHelp also lists interactions of Zafirlukast with, for example, Pimozide, Lomitapide, Nilotinib. The full list is on the Zafirlukast page.
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