ORLANDO, Fla. (Ivanhoe Newswire) -- Diabetics who are taking rosiglitazone
(Avandia), which is one of a new generation of treatments for type 2 diabetes,
should not also take St. John's wort, reveals a new study presented at the
annual meeting of the American Society of Pharmacology and Therapeutics in
Study author Matthew Hruska, PharmD, from the University of Florida College
of Pharmacy in Gainesville, explains that many patients with diabetes turn to
alternative therapies including St. John's wort, a popular herbal remedy used to
treat mild depression and insomnia. In previous studies, St. John's wort has
shown to increase the clearance of a number of drugs.
Hruska and his colleagues set out to investigate the effect of St. John's
wort on how rosiglitazone is metabolized in the body. Twenty-seven participants
received eight milligrams of rosiglitazone in the presence and absence of 900
milligrams of daily St. John's wort. After examining blood and urine samples,
researchers found that St. John's wort hastens the elimination of rosiglitazone
from the body, so that less of the drug remains to help control blood sugar.
"Patients with diabetes should talk with their doctors or pharmacists about
any herbal products they are taking or plan to take, so that potentially harmful
interactions can be identified and avoided," Hruska concludes.
SOURCE: Amanda Jackson at the annual meeting of the American Society for
Clinical Pharmacology and Therapeutics in Orlando, Fla., March 2-6, 2005