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. Last Updated: 07/27/2016

St. John's Wort Returns as Hottest Herbal Remedy

WASHINGTON -- Sandra Gonnell was feeling stressed out by her job as a nurse practitioner in a busy Dallas clinic, but she hated the idea of taking a prescription drug like Prozac to improve her mood. Then last spring, Gonnell, 41, heard about St. John's wort, an ancient medicinal herb that is gaining popularity as an over-the-counter treatment for depression.

"I thought, 'Well, I'm going to try that,'" Gonnell said. She found a bottle of pills containing the herbal extract at her local supermarket and began taking one or two a day. After two or three weeks, it seemed to her that she was starting to feel better.

"It just takes the edge off things," said Gonnell, who has been taking St. John's wort for about three months. She said when her co-workers at the clinic start complaining about their jobs, it doesn't bother her as much as it used to. "Now, I just say, 'That's the way they are -- that's fine.' It seems like it's easier to do now."

St. John's wort, or Hypericum perforatum, a weed whose medicinal history dates back to Hippocrates and Pliny the Elder, has lately become the hottest herbal remedy in supermarkets and health-food stores -- and in the case of this particular herb, there's considerable scientific evidence backing up the claims of therapeutic value.

Although the plant may not entirely deserve its nickname of "natural Prozac," German and U.S. researchers who reviewed 23 European studies of St. John's wort last year concluded it seemed to work about as well as some of the older prescription antidepressant drugs for treating mild to moderate depression -- and with fewer side effects. In Germany, where hypericum extract is a prescription drug, almost 3 million prescriptions are filled each year.

The problem is that nobody yet knows exactly how it works, what the optimal dose is or even which chemicals in the plant are the active ingredients. Numerous brands are on the U.S. market, and psychiatrists say the amounts of chemicals they contain probably vary from brand to brand and from one batch to the next.

National Institutes of Health officials are sufficiently impressed by the potential of St. John's wort to fund a $4.5 million, three-year study of its effectiveness, in which it is to be compared with a placebo and with the potent antidepressant sertraline Zoloft. But meanwhile, doctors are concerned about the number of people who are taking it without medical supervision.

They worry that seriously depressed people may use it to avoid seeking more definitive help. At the same time, they fear some consumers may suffer unexpected side effects, particularly if they take St. John's wort in addition to other prescription drugs.

"It actually has made me a little nervous," said Una McCann, chief of the anxiety disorders unit at the National Institute of Mental Health. "I think a lot of people are under the impression that because something is 'natural,' it can't do any harm -- that you can take it with abandon on top of anything else you're taking. ... That's a very dangerous perception."

The debate over St. John's wort also touches on the question of which substances should be considered drugs. Foxglove and willow bark were used as traditional herbal remedies for centuries before chemists isolated digitalis and aspirin as their active ingredients. Mood-altering plant products such as coffee, tea, beer and tobacco have long been part of U.S. culture, and none are currently regulated as drugs, although pure preparations of caffeine and nicotine are.