Does Grapefruit Affect Fisetin?

Amount or timing may matter

The short answer

Fisetin is metabolized by CYP3A4 and also inhibits P-glycoprotein. Grapefruit may cause additive enzyme inhibition and increase fisetin levels.

How to arrange timing

Separate fisetin from grapefruit by at least 4 hours.

Reference

Reference noted for this food and supplement combination: Examine.com; Syed et al., Biochem Pharmacol 2013

Important context

The effect can also change with food amount, supplement dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.