Answer
Grapefruit juice should be avoided within 24 hours before taking avanafil because it inhibits CYP3A4 and would likely increase avanafil exposure, although the specific interaction has not been studied.
Sources for this answer
- Spedra 50 mg tabletsA. Menarini Farmaceutica Internazionale SRL · emc · SmPC §4.5 Interaction with other medicinal products · Version 11Document updated
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