St. John's wort research

From the American Academy of Family Physicians, http://www.aafp.org/afp/20051201/2249.html:

"A Cochrane Systematic Review9 used specific criteria to examine the use of St. John's wort for depression. Study limitations included heterogeneous diagnoses of depression, short trial durations, and low dosages of standard antidepressants in comparison trials. In all but one of the 27 clinical studies (n = 2,291) of different hypericum preparations, investigators concluded that St. John's wort was either more effective than placebo or as effective as older pharmaceutical antidepressants in the treatment of mild to moderate depression.

More recently, 13 additional clinical trials have been published, some of which, along with a Cochrane review, are summarized in Table 1.9-19 In 10 of these studies, investigators found that St. John's wort was superior to placebo11,16,20-22 or as effective as standard antidepressants (e.g., amitriptyline [Elavil],10 fluoxetine [Prozac],12,13 imipramine [Tofranil],11,14 sertraline [Zoloft]15) in the treatment of mild to moderate depression. Two updated meta-analyses exploring the effectiveness of St. John's wort for the treatment of depression are based on studies published between 1979 and 2003.23 Although their results suggest the possibility that St. John's wort may be less effective than previously assumed, the meta-analyses indicated that St. John's wort was significantly more effective than placebo (risk ratio for first meta-analysis: 1.97, 95% confidence interval [CI], 1.54 to 2.53; risk ratio for second meta-analysis: 1.73, 95% CI, 1.40 to 2.14).

Studies17-19 on the use of St. John's wort in patients with major depression have had conflicting results.According to the results of one double-blind, placebo-controlled, multi-center clinical trial18 (n = 200), St. John's wort was effective in treating outpatients with major depression. Although the number of patients achieving remission in symptoms of depression was significantly higher with St. John's wort therapy than with placebo (P = .02), overall remission rates were low (14.3 and 4.9 percent, respectively).

[SOME NEUTRAL REPORTS] The Hypericum Depression Trial Study Group conducted a double-blind, randomized controlled trial19 (n = 340) in 12 academic and community psychiatric research clinics in the United States. Investigators found that St. John's wort and sertraline did not differ from placebo for major depression outcomes or adverse events. The authors of an earlier study17 (n = 209) concluded that St. John's wort was equivalent to imipramine in patients with severe depression.

Taken together, the data10-22 continue to support the overall conclusions of the Cochrane review,9 as well as other published reviews,24,25 that St. John's wort is more effective than placebo and as effective as standard antidepressants for the treatment of mild to moderate depression. "