NASHVILLE, TENNESSEE. Numerous clinical trials have attested to the effectiveness of St. John's wort (Hypericum perforatum) in the treatment of mild to moderate depression. A team of researchers from 11 American universities now concludes that St. John's wort is not effective for the treatment of major depression. Their randomized, double blind trial included 200 adult outpatients (mean age of 42.4 years, 67 per cent female) who had a baseline Hamilton Rating Scale for Depression (HAM-D) score of at least 20. After a one-week run-in on a placebo 98 of the participants were assigned to receive 900 mg/day of St. John's wort extract (increased to 1200 mg/day if no effect after four weeks) or a placebo for a total of eight weeks. At the end of the experiment 26.5 per cent of the members of the St. John's wort group showed a positive response (HAM-D rating less than 12) as compared to 18.6 per cent in the placebo group. The researchers deem this difference to be statistically insignificant. They did conclude though that the remission rate (HAM-D score less than 7) in the St. John's wort group was significantly greater at 14.3 per cent than in the placebo group (4.9 per cent). Nevertheless, their overall conclusion is that St. John's wort is not effective in the treatment of major depression. NOTE: This study was funded and partially designed by Pfizer Inc., a major manufacturer of pharmaceuticals. Thirteen of the 16 researchers involved in the study had received funding from Pfizer and other pharmaceutical companies.
Shelton, Richard C., et al. Effectiveness of St. John's wort in major depression: a randomized controlled trial. Journal of the American Medical Association, Vol. 285, April 18, 2001, pp. 1978-86 [58 references]