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antidepressants used as active controls for comparison, and lack of research on the risk of
serotonin syndrome when St. John’s wort is combined with other anti-depressants.
Serotonin syndrome is a serious condition defined by muscle rigidity, fever, confusion,
increased blood pressure and heart rate, and coma. See Major Risks, below.
- PREPARATION: The flowering tops of St. John’s wort are used to prepare teas and tablets
containing concentrated extracts. There is no standardized extract of St. John’s wort, but
Mischoulon and Rosenbaum report that most studies use a formula of 0.3% hypericin or
hyperforin (the actual active ingredient is unknown), and the Schwabe company has
recently tested its proprietary St. John’s wort formula (WS 5570) with success in treating
more severe depression. It is urgent that more testing be done and that a standardized non-
proprietary extract be developed for further study. Berkeley Wellness cautions that
formulas vary widely in the amount and bio-availability of hypericin or hyperforin and that
contaminants can be a problem.
- POTENTIAL USES: According to NCCAM, St. John’s wort is used for severe depression,
anxiety, and sleep disorders, though the available evidence supports only its use for mild to
moderate depression. A few randomized controlled studies show beneficial effects of John’s
wort for treatment of somatization disorder (similar to hypochondria, transferring
emotional conditions to physical symptoms) and seasonal affective disorder. It has also
been tested (unsuccessfully) for use to relieve irritable bowel syndrome.
- EFFICACY: MILD TO MODERATE DEPRESSION: Eight sources consulted for this outline
agree that St. John’s wort is better than placebo and possibly as effective as tricyclic
antidepressants and SSRIs in treating short-term mild to moderate depression.
Fugh-Berman and Cott found St. John’s wort to be an evidence-based treatment for mild
to moderate depression, relying principally on a 1996 meta-analysis evaluating twenty-
three randomized trials of St. John’s wort (of which twenty were double-blind) involving
1757 patients with mild to moderate depression.^1 “Improvement in depressive
