Avanafil and Isosorbide mononitrate interaction
Avanafil and Isosorbide mononitrate: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Avanafil label · effective 2025-12-17
• Administration of avanafil tablet to patients using any form of organic nitrate is contraindicated ( 4.1 )
Nitrates Administration of avanafil tablets with any form of organic nitrates, either regularly and/or intermittently, is contraindicated.
Consistent with its known effects on the nitric oxide/cyclic guanosine monophosphate (cGMP) pathway, avanafil has been shown to potentiate the hypotensive effects of nitrates.
In a patient who has taken avanafil tablets, where nitrate administration is deemed medically necessary in a life-threatening situation, at least 12 hours should elapse after the last dose of avanafil tablets before nitrate administration is considered.
In such circumstances, nitrates should only be administered under close medical supervision with appropriate hemodynamic monitoring [see Contraindications ( 4.1 ), Dosage and Administration ( 2.3 ), and Clinical Pharmacology ( 12.2 )].
From the Isosorbide mononitrate label · effective 2019-11-01
Do not use isosorbide mononitrate in patients who are taking certain drugs for erectile dysfunction (phosphodiesterase inhibitors), such as sildenafil, tadalafil, or vardenafil.
Drug Interactions Concomitant use of isosorbide mononitrate with phosphodiesterase inhibitors in any form is contraindicated (see CONTRAINDICATIONS).
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.