News & Perspectives

Perspective on St. John's Wort: Is it Effective for Depression?
Over the last few years, the bright yellow-flowered herb St. John's wort has gained a reputation as a safe and effective alternative to prescription drugs like Prozac, which are widely prescribed for depression. Now the effectiveness of this popular herb is being called into question by a major new study published in the prestigious Journal of the American Medical Association (4/18/01).

The JAMA study is the first large-scale trial on St. John's wort and depression conducted in the United States. Drawing from medical centers around the country, it involved 200 adults whose depression was, without question, severe.

Participants were given either a placebo (dummy drug) or St. John's wort (900 mg a day). If no improvement was seen in four weeks, the dose was increased to 1,200 mg a day for an additional four weeks. Neither the investigators nor the patients in this double-blind study knew if they were receiving the herb or a placebo.

Upon pooling the results, the investigators declared that St. John's wort was no better than a placebo in alleviating major depression, which can be a life-threatening illness because there's often a risk of suicide attached.

Depression level is key
Widely extolled for its effects, St. John's wort is now used by an estimated 1.5 million Americans; in 2000, consumers spent some $195 million to buy products containing this herb. Given these numbers and the conclusions of this new study, the question becomes: Should everyone stop taking St. John's wort? Is it effective or just a waste of money?

"Whether or not you should use St. John's wort depends largely on the severity of the depression to be treated," explains David Edelberg, M.D., a leading integrative physician and the chief medical advisor of WholeHealthMD. "This study looked at patients with serious depressive symptoms. In our experience, this herb works best for milder problems. People with severe depression need a higher level of care--meaning prescription antidepressants and often psychotherapy as well."

Few sources, in fact, have ever claimed that St. John's wort will work for severe depression. It is the herb's effectiveness for mild to moderate depression that has been widely demonstrated in numerous studies. German health authorities approve of it for this use, and recently, a large trial from Germany found the herb to be as beneficial--and far better tolerated--than the tricyclic antidepressant drug imipramine (British Medical Journal, 9/2/00).

Attitude counts
There are a number of additional mitigating factors. Any doctor or researcher can tell you that a person's state of mind (whether positive or negative) can affect the outcome of a treatment--commonly known as a placebo effect. This phenomenon is so strong that many doctors actively promote a positive attitude in their patients, and scientists designing an experiment routinely correct for the bias it creates by including a control group or by doing a double-blind study.

According to Dr. Edelberg, "Most successful users of St. John's wort very specifically do not want to be on chemical antidepressants. So when they're taking St. John's wort, they are psychologically quite motivated to have a positive response." In the JAMA study, participants were not seeking out alternative or herbal therapies; they had simply agreed to be part of a research project.

The JAMA investigators acknowledge that some of those (14.3%) taking St. John's wort (compared with 4.9% on the placebo) did see a reduction in their depressive symptoms. Even though this rate was too low to be declared a clinically useful treatment for severe depression, it does indicate that the herb works for some people and is thus an encouraging finding for those with milder symptoms.

More studies needed
Despite this new study, research is still lacking on how St. John's wort compares with the newer SSRI antidepressants, like Prozac, or to depression-fighting supplements like SAM-e. "When we planned our study four years ago," says herbal researcher Dr. Karl Hiller of Germany, "imipramine was considered the gold standard in antidepressants in Germany, so that's what we compared it to."

A three-year, NIH-funded study comparing St. John's wort and the widely prescribed antidepressant Zoloft is currently under way at Duke University. And further research is needed on herb-drug interactions and on herbal side effects. Still, many experts feel St. John's wort is safer and gentler than most prescription drugs.

Consider symptoms carefully
Assessing your symptoms is critical when considering the usefulness of St. John's wort for depression, an ailment for which the spectrum--from feeling mildly blue to feeling suicidal--is wide indeed. "If you believe that your depression symptoms are beginning to interfere with your day-to-day functioning as a person, then it's probably time to get some professional help," says Dr. Edelberg. He cites such symptoms as not showing up for work or school, sleep disturbances, compulsive overeating, and feelings of increasing isolation as reasons to see the doctor.

The bottom line here is the JAMA study has confirmed what physicians familiar with St. John's wort already knew, namely, that the herb is simply not strong enough to be a good choice for severe depression. However, for mild-to-moderate depression, St. John's wort remains reliable, safe and effective.

Cautions: Always see a physician if you're depressed. Tell your doctor of any herbs you are taking. Don't combine St. John's wort with other antidepressants, such as Prozac or Zoloft. And report any unusual symptoms that arise.

Suggested dose for mild depression: 300 mg, three times a day, with meals. Some newer preparations allow twice-daily dosing: 450 mg twice a day. Like prescription antidepressants, St. John's wort needs to build up in your system to be effective. Therefore, you may need to take the herb regularly for at least four to six weeks before you notice improvement. If, after four weeks you see no improvement at all, increase the dose to 1200-1350 mg a day.

Date Published: 04/30/2001

> Printer-friendly Version Return to Top