The simmering debate over the role of the troubled herbal medicine St John’s wort (Hypericum perforatum) in the treatment of depression boiled over again today following publication of results from a large American study designed to evaluate the drug’s effectiveness in people with major depressive disorder (MDD). The trial appears in this week’s Journal of the American Medical Association, and coincides with the launch of NAM’s Directory of Complementary Therapies in HIV & AIDS, a new resource which provides a rigorous review of scientific evidence regarding the efficacy of complementary therapies in both HIV disease and in general medicine.
Davidson and colleagues from the Hypericum Depression Trial Study Group sought to compare the effects of St John’s wort with placebo, and with sertraline (Zoloft™, Lustral™), a licensed antidepressant from the SSRI class, in adults with major depression. Three hundred and forty people were randomised to receive one of the three treatments, in blinded fashion, for an eight week period. The trial’s main outcome measure was the change in an established gauge of depression, the Hamilton Depression Scale (HAM-D) score, between entry and this eight week time-point. Those responding to treatment were then eligible for an eighteen week continuation phase.
Though media reporting of the study has focused almost exclusively on the lack of efficacy observed in those receiving St John’s wort, the trial found no difference in response between both St John’s wort and sertraline, compared to placebo. After eight weeks treatment, a full response occurred in 31.9% of placebo recipients, 23.9% of St John’s wort recipients, and 24.8% of sertraline-treated participants. These differences are not statistically significant. In relation to a secondary endpoint, the change in Clinical Global Impressions (CGI) score, sertraline performed better than placebo.
Whilst most users of St John’s wort in the UK and USA buy the drug over-the-counter, it is a licensed medicine which can be prescribed for the treatment of depression in Germany.
Though this new trial found the drug ineffective in major depression, previous studies, and three systematic reviews have concluded that St John’s wort is more effective than placebo in treating milder forms of depression.
The drug attained a certain infamy in the HIV field in 2000 following a case report of anti-HIV treatment failure due to an interaction between the protease inhibitor indinavir, and St John’s wort.
The UK’s Medical Control Agency subsequently warned against the use of St John’s wort alongside protease inhibitors, NNRTIs, and a wide range of medications which share the same metabolic pathway through the liver.
Herbalism is one of twenty-one popular forms of Complementary Medicine reviewed in NAM’s Directory of Complementary Therapies in HIV & AIDS. Edited by NAM Senior Editor, Anna Poppa, the Directory is now available from NAM at the price of £15.00 to professionals, and is free to people with HIV.
Hypericum Depression Trial Study Group. Effect of hypericum perfortaum (St John’s
wort) in major depressive disorder: A randomized controlled trial. JAMA
2002;287:1807-1814.
Linde K et al. St John’s wort for depression: an overview and meta-analysis of
randomised clinical trials. BMJ 1996 Aug 3;313(7052):253-258.
Linde K et al. St John’s wort for depression. Cochrane Database Syst Rev
2000;(2):CD000448.
Gaster B et al. St John’s wort for depression: a systematic review. Arch Intern
Med 2000 Jan 24;160(2):152-6.
Piscitelli S et al. Lancet 2000;355:547-548.