Does Grapefruit Affect CBD (Cannabidiol)?

Amount or timing may matter

The short answer

CBD is extensively metabolized by CYP3A4 and CYP2C19. Grapefruit can increase CBD blood levels, amplifying sedation and potential side effects.

How to arrange timing

Separate CBD from grapefruit by at least 4 hours. Monitor for increased drowsiness.

Reference

Reference noted for this food and supplement combination: Nasrin et al., J Pharmacol Exp Ther 2021

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.