St. John's wort for depression

The debate over the effectiveness of St. John’s Wort in fighting depression now has added fuel. 

Three recent clinical trials from 2005 and 20061-3 and a critical review of the literature (2006)4 have examined whether the herbal supplement is an effective treatment for depression. The data all indicate that St John’s Wort is indeed safe and effective for people who are mild to moderately depressed. The evidence on how it affects moderate-to-severe depression remains unclear.

This is particularly newsworthy because two prior studies—including a 2002 study sponsored by the National Center on Complementary and Alternative Medicine at the National Institute of Health5,6—suggested that St. John’s Wort was no more effective than a placebo in treating mild to moderate depression.

Hyla Cass, M.D., chairwoman of complementary and alternative medicine at the American University of Complementary Medicine in Los Angeles, maintains that in her own practice of using St. John's Wort she has found that people “respond well and really appreciate the lack of side effects and not feeling 'medicated.' "

Contrary to U.S. medical practice, St. John’s Wort is already used extensively in Western Europe. In Germany, for example, doctors often turn to traditional antidepressants only after a trial of St. John’s Wort has not been successful. 

St. John’s ‘What?’

St. John's Wort (Hypericum) is a roadside weed that has been used for centuries to treat a variety of disorders. In 350 B.C., the Greek physician and writer Hippocrates prescribed the herb’s extracts for relief from such ailments as dysentery, tuberculosis, malaria, hemorrhage, jaundice, colds, insomnia and hysteria. Today, St. John's Wort is used primarily to relieve the symptoms of depression, anxiety and sleep disorders.

The flowering tops of St. John's Wort are used to prepare teas and tablets containing concentrated extracts of the active ingredients hypericin or hyperforin. The extracts are standardized to 0.3 percent hypericin, with a typical adult dose of 300 milligrams 3 times a day (yielding 2.7 mg hypericin per day). Preparations available in the United States contain inconsistent amounts of active ingredient, so be sure to read labels to know exactly how much you're actually getting in your tablet or tea.

Many folks who regularly take St. John’s Wort note improvements in overall mood and sleep. Researchers believe that the antidepressant effect of St. John’s Wort is due to its inhibition of serotonin uptake by certain receptors in the brain—the same mechanism attributed to many widely prescribed antidepressants.7

Although St. John’s Wort is generally considered safe, it can cause undesirable interactions with herbs, other supplements or prescription medicines, including theophylline and digoxin. The U.S. Food and Drug Administration (FDA) recommends that St. John's Wort not be used with any type of antiretroviral medication used to treat HIV or AIDS. 

St. John’s Wort is not to be used if you’re pregnant or nursing. New data presented at the 21st Annual Meeting of the American Association of Naturopathic Physicians (August 2006) suggest that St. John’s Wort might interact with medications prescribed during pregnancy and might cause lower infant birth weights.8

And if you currently use a prescription antidepressant, do not take St. John’s Wort without speaking to your health care provider first. When combined with some antidepressants, St. John’s Wort can result in a serotonin overload, causing sweating, agitation and confusion.

Proceed With Caution

Jonathan Davidson, M.D., director of the Anxiety and Traumatic Stress Program at Duke University, says that “rather than self-medicate with an over-the-counter medication or supplement, patients are strongly advised to consult an appropriate health care provider to assess the best treatment for a depressive episode.”

In its advice to consumers, the National Center for Complementary and Alternative Medicine has the following recommendations for people interested in trying St. John’s Wort:

• Use only under the supervision of your health care provider, in recommended doses.
• Do not mix with other drugs and antidepressants, except under the supervision of your health care provider.
• Be mindful of exposure to sunlight (and possible burning), especially if you are fair-skinned.
• Do not expect instant results. Like other antidepressants, St. John’s Wort requires several weeks before its antidepressant effects take hold.
• Keep your expectations realistic. There is no real evidence that St John's Wort is effective in treating major depression.