A popular herbal product called kava kava, said to relieve anxiety and stress, is having an anxious time of it itself. German scientists have linked it with 30 cases of liver disease. Six of the victims experienced liver failure. One died, and four others required liver transplants. Switzerland and France promptly banned its sale. Germany warned manufacturers that it might do the same. And Britain asked for kava kava’s temporary withdrawal from the market.

In the United States, such items are almost totally free of regulation, exempted by a 1994 law.

Kava kava has been used by Pacific island people for 3,000 years as a ceremonial drink and as a remedy for anxiety disorders and depression. The plant, of the pepper family, grows as a bush with large heart-shaped leaves. The natives pounded or chewed the root and mixed it with water to make a brownish drink to calm their nerves and combat fatigue. Some advocates claim that it is a good treatment for venereal disease, gout, rheumatism, bronchitis and aches and pains. Some think it improves sexual desire and prowess.

The product is sold in most U.S. pharmacies and health food stores as teas of various brands and in capsules as a “dietary supplement.” Its popularity has soared in the past five years, with annual sales now reported at $34 million.

Here in eastern Maine, opinions of kava kava are mixed. Many users praise it as a soothing remedy for stress. But an herbalist in one area health food store said he “wouldn’t touch it with a 10-foot pole.” He tried it once, and it gave him the rash of his life. He warns customers not to take it too long at a time and to watch for side effects.

Labels on some of the tea packages and on most capsule bottles warn in tiny print that no one should use kava kava who is younger than 18, pregnant, nursing or being treated for depression. The labels also warn against driving a vehicle or operating heavy machinery. Alcohol can increase the effects of kava kava. Maine’s public health director, Dr. Dora Anne Mills, urges that no one take kava kava or any other “so-called supplements” without checking with a doctor. “They are really unlabeled drugs, with potentially very harmful effects. They should be regulated, the same as all other drugs.”

The original Food and Drug Administration law of 1908 covered dietary supplements as well as food additives and prescription and over-the-counter drugs. But the 1994 Dietary Supplement and Health Education Act largely exempted the supplements, which have exploded in popularity into a $15 billion a year industry. The 1994 legislation does retain some restrictions. Companies can’t imply that a product treats or prevents a disease, although they can claim, for example, that a substance helps keep the prostate working normally. Such claims must be submitted to the Food and Drug Administration, and companies are required to say on their labels that the agency hasn’t evaluated their claims.

In the case of kava kava, the most the agency can do right now is study cases of apparently related illness. That may take another year. If the agency should finally determine that the product is harmful, it could then order it off the market. Is that enough protection for the consumer? Congress seems to think so, and the American public generally seems to want freedom to try remedy classified as “natural.” But at the very least, a follow-up on the liver-disease study is warranted here.