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St. John's Wort Trumps Depression Drug

Sept. 1, 2000 -- So, many of you may have heard that St. John's wort works for milder depression, right? But, does it really? Study results to date have been conflicting. But a recent German study says it really does the trick, when compared with an older antidepressant. So, is that the final answer? Nope: U.S. experts remain cautious about research findings and warn that there are lots of other problems associated with taking the herb.

"In this study we investigated more than 300 patients with mild to moderate depression -- this is very important: it did not include severe depression. We compared two groups: one group received a well-known synthetic antidepressant drug, imipramine [one of its trade names is Tofranil] and the other group received St John's wort extract," study author Helmut Woelk, tells WebMD. "We found that therapeutically there was almost no difference in effectiveness for treating mild to moderate depression, but the rate of side effects was much lower in the [St. John's wort] group." Woelk is the medical director of the Clinic for Psychiatry and Psychotherapy and a professor of psychiatry at the University of Giessen in Germany.

In the study, published in the Sept. 2 issue of the British Medical Journal, Woelk and colleagues randomly divided 324 patients with mild to moderate depression into two groups: one group got imipramine, which is among an older group of antidepressant drugs called tricyclic antidepressants, twice daily for six weeks, and the other got St. John's wort extract twice daily for six weeks.

Patients improved on both treatments, and to the same extent, but nearly two-thirds of the patients taking imipramine reported side effects, compared to just over a third of those taking St. John's wort. Side effects caused 16% of patients taking the antidepressant and 3% of patients taking St. John's wort to drop out. Some of the common side effects noted for the antidepressant are dry mouth, nausea, dizziness and sweating.

"The study is important because there are a lot of patients -- millions worldwide -- with mild to moderate depression," says Woelk, noting that the World Health Organization estimates 3% to 5% of the population suffer from it. "These patients could take [St. John's wort] instead of synthetic compounds with [more] side effects -- and a lot of patients interrupt their treatment because of the side effects. So one can say [St. John's wort] could be a first-line treatment for this group of depressives."

In fact, Woelk expands the possibilities of the herb to the newer antidepressants by saying he's seen patients drop out from side effects from both the older and the newer versions of the synthetic drugs.

But St. John's wort still remains to be tested head-to-head against the new group of antidepressants, called selective serotonin reuptake inhibitors, such as Prozac, and other new compounds.