STOCKHOLM (Reuters) – St. John’s wort, an herbal product used to treat mild depression, may counter the effect of oral contraceptive pills (OCPs) and has led to at least two unwanted pregnancies in Sweden, the country’s pharmaceuticals authority said.
The Medical Products Agency said on its Web site that taking St. John’s wort had resulted in two OCP users becoming pregnant. Similar cases have been reported in Britain, it said.
An agency official said Sweden had already introduced a warning label on certain types of St. John’s wort products at the end of 1999 after studies showed these products could interact strongly with drugs.
Now a similar warning will be placed on all other kinds of St. John’s wort products except tea, Barbro Gerden told Reuters. “It is still popular but I think the warnings we have put out before have affected sales in Sweden,” she added.
Health authorities in several countries have said that St. John’s wort may counter the effect of antiretrovirals, anticoagulants, and cyclosporine.
The problem was that despite the labeling in Sweden, several women did not consider OCPs to be drugs, Gerden said. “Considering the number of women this is affecting, this is important information,” she added.