St. John’s Wort
This article was originally published in The Tan Sheet
Executive Summary
A systematic review of prospective clinical trials evaluating the pharmacokinetic effect of St. John's Wort on the metabolism of conventional drugs found 17 of 19 trials with available plasma data showed a decrease in bioavailability of the conventional drug. The review by Edward Mills, McMaster University Hamilton, Ontario, et al., looked at 22 pharmacokinetic trials overall, averaging 12 participants. The report, published in the July 3 British Medical Journal, concludes that clinicians and patients "should beware of possible decreases in the systemic bioavailability of conventional drugs" taken with the botanical...