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symptoms (usually measured by the HAM-D or Clinical Global Impression scale) was
observed in all groups. In 15 placebo-controlled trials, St. John’s wort was found to be
significantly more effective than placebo. In eight treatment-controlled trials (i.e.,
trials contrasting St John’s wort with an active clinical agent), clinical improvement in
those receiving St. John’s wort did not differ significantly from those receiving tricyclic
antidepressants.”^2
Brown et al. note that recent studies support the efficacy of St. John’s wort in treating
mild to moderate depression. However, they do not recommend it as a first line
treatment because of the incidence of phototoxicity (1%) and the risk of medication
interactions. However, they note that people with a history of good response to low-
dose SSRIs but intolerable side effects such as weight gain or sexual dysfunction,
would be better candidates for St. Johns wort.^3
Mischoulon and Rosenbaum are more positive: St. John’s wort, "has demonstrated
superior efficacy to placebo and equal efficacy to low dose tricyclic antidepressants in
most of the older controlled trials, but has had more mixed results against the SSRIs
and placebo in some of the newer, large-scale studies. The most recent studies have
generally shown St. John’s wort to be more effective than placebo, equal to
antidepressants, and able to prevent depressive relapses.”^4
However, they conclude that: “Because the literature as a whole suggests that St.
John’s wort may be less effective in cases of more severe or more chronic depression,
the best candidates for St. John’s wort may be those with milder and more acute
forms of depression.”^5
Lake and Spiegel (by Yee, Yee and Naing) concur that there is “compelling evidence” for
the use of St. John’s wort in mild to moderate depression, terming studies in more
serious depression “inconclusive.”^6
The Natural Standard concurs that: "Numerous studies report St. John’s wort to be
more effective than placebo and equally effective as tricyclic antidepressant drugs in
the short term treatment of mild to moderate major depression (1-3 months.)”^7 The
focus on short-term use is significant. One of the most significant research gaps is lack of