Does Grapefruit Affect Cat's Claw?

Amount or timing may matter

The short answer

Cat's claw alkaloids are CYP3A4 substrates. Grapefruit may increase their blood levels and amplify immunomodulatory effects.

How to arrange timing

Separate cat's claw from grapefruit by at least 4 hours.

Reference

Reference noted for this food and supplement combination: Examine.com; Heitzman et al., Planta Med 2005

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.