Herbal supplements come under the gun

Doctors applaud Europe's call for warning labels on St. John's wort, and the Food and Drug Administration moves on kava kava.

By Victoria Stagg Elliott, amednews staff. March 4, 2002.

The news is enough to make purveyors of kava kava and St. John's wort anxious and depressed, but it's putting some pep in the steps of physicians. The U.S. government and others are increasing their scrutiny of the largely chaotic world of herbal dietary supplements.

The Food and Drug Administration wants to hear from physicians about adverse events among patients related to kava's use.

Elsewhere, Sweden is now requiring warning labels on St. John's wort about the possibility that it causes the birth control pill to fail. Several European countries have banned kava.

Physicians on all sides of the debate about complementary and alternative medicine generally applauded the governments' moves. But many said the steps don't go far enough. Some want more accessible education for both consumers and physicians. Many doctors, however, want much more regulation and, at the very least, more information on supplements' labels to bring them in line with those on pharmaceuticals.

Sweden requires warnings that St. John's wort may cause the birth control pill to fail.

Tim Gorski, MD, points to St. John's wort. In addition to interfering with the birth control pill, the herb is suspected by some of interfering with HIV medicines, transplant drugs and anti-depressants.

The warning label in Sweden "is a great idea, but it doesn't go far enough," said Dr. Gorski, associate clinical professor of obstetrics and gynecology at the University of North Texas Health Science Center in Fort Worth. "St. John's wort is very obviously something that's being taken as a medication ... and the idea that this is a 'supplement to the diet' and should be regulated any differently from Prozac or the rest of them is ridiculous."

Keeping an eye on kava

As for kava, the FDA action is in response to 38 adverse event reports connected with the substance, including one involving a person who needed a liver transplant.

Those who specialize in complementary and alternative medicine have long known about the possible liver toxicity of high doses of kava. Some suspect that overdoses are now easier because herbal supplements have been sneaking their way into foods and drinks.

"You can stop at any convenience store or gas station and buy yourself a kava drink," said Bernd Wollschlaeger, MD, medical director of the Aventura Family Health Center, North Miami Beach, Fla. Dr. Wollschlaeger uses supplements in his medical practice and tries to educate other physicians about the topic. "People think it's natural. 'It's safe, therefore, I don't have to mind the dosage.' "

FDA action on kava follows 38 adverse events, one involving liver toxicity.

The FDA is investigating, but the situation is complicated by the nature of the supplement market.

"The appearance of an adverse event report does not mean it's conclusive," said an FDA spokesman. "The numbers may be artificially inflated, because it may turn out that there is no kava in the product, despite what it says on the label."

But the explosion of the herbal supplement market and the accompanying government regulation has also led to more research that many say is desperately needed.

"We are just swinging from one extreme to the next," said Dr. Wollschlaeger. "First we embrace the plants, and now we condemn them because they have similar effects to pharmacological substances."

There is some information about possible interactions and adverse events but many doctors say there is not nearly enough for them to work with.

"We should caution our patients about the potential interactions," said Dr. Wollschlaeger. "We know there is a potential risk, but not whether it's high, medium or low."

Until there is more information and education, physicians emphasized that it is important to ask patients what they are taking in addition to prescription or over-the-counter drugs.

"It's so important to know what they're on besides the traditional pharmacologic medicines," said Nancy Church, MD, an obstetrician-gynecologist at the Wellness Connection in Chicago.