Supplementation with goldenseal (Hydrastis canadensis), but not kava kava (Piper methysticum), inhibits human CYP3A activity in vivo
Gurley BJ, Swain A, Hubbard MA, Williams DK, Barone G, Hartsfield F
Published in Clinical Pharmacology & Therapeutics
Methodology
Open-label crossover pharmacokinetic study in 16 healthy volunteers using midazolam as a CYP3A phenotypic probe before and after 14 days of goldenseal supplementation
Key Findings
Goldenseal increased midazolam area under the curve by 40-60%, indicating clinically relevant CYP3A inhibition; kava kava had no effect.
Conclusions
Goldenseal is a clinically significant inhibitor of CYP3A and can raise blood levels of many prescription drugs.
Limitations
Small healthy-volunteer sample; single probe drug; product-specific alkaloid content.
Supplements Studied
Goldenseal supplementation produced significant inhibition of CYP3A activity, increasing midazolam exposure in healthy volunteers.
Kava kava did not inhibit human CYP3A activity in vivo.
Study Details
Access Study
This information is for educational purposes only. Always consult a healthcare professional before starting any supplement regimen.