DesignDescriptionComments
RCT with St. John's wort in OCDCompared 30 patients with OCD taking LI 160 extract (range: 300 to 1,800 mg) and 30 patients with OCD taking placebo for 12 weeks16; St. John's wort had no effect on reducing Yale-Brown Obsessive-Compulsive Scale total or subscale scoresAgitation side effect more common with St. John's wort
Open, uncontrolled study of St. John's wort in OCDSignificant reductions in the Yale-Brown Obsessive-Compulsive Scale score in 12 patients with OCD starting one week into the study and continuing throughout the 12-week trial17; the compound used was a 450-mg, extended-release formulation of 0.3% Hypericum taken two times a weekThe small number of patients and lack of comparison to placebo make this evidence weak; few side effects reported
RCT with St. John's wort in social phobiasCompared flexible doses of LI 160 extract (range: 300 to 1,800 mg twice a day) and placebo in 40 patients with social phobias18; St. John's wort had no effect in reducing anxiety scoresSide effects no worse than placebo
RCT with St. John's wort in somatoform disordersSt. John's wort was used to treat somatoform disorders using reductions in the Hamilton Anxiety Scale somatic anxiety subscale score as the primary outcome measure19; after patients with significant depressive symptoms were excluded, 150 patients were randomized to St. John's wort or placebo; dosage of the LI 160 extract was 300 mg twice a daySomatoform disorders have complex relationship with anxiety disorders
Results showed a strong positive effect of St. John's wort, compared with placebo, in reducing somatic anxiety, psychic anxiety, overall anxiety scores, and physician and patient ratings of somatoform disorder symptoms
Open trial with St. John's wort plus valerian in anxiety and depressionValerian was used in combination with St. John's wort to treat patients with comorbid anxiety and depression; the combination was better than St. John's wort alone at reducing anxiety scores20 Suggestive improvement of St. John's wort with addition of valerian; very few side effects
RCT with valerian versus diazepam (Valium) and placebo in GADRandomized, double-blind, placebo-controlled comparison of valerian with diazepam in GAD, 12 patients per group for four weeks21; no differences between valerian and placebo, or between diazepam and placeboToo underpowered to demonstrate differences in effectiveness; no differences in side effects
RCT with Sympathyl versus placebo; two tablets twice a day in GADDouble-blind randomized trial conducted among patients with mild to moderate GAD in 22 general practices in Paris, France22; Sympathyl (n = 130) and placebo (n = 134) groups were relatively large; after three months the Sympathyl group showed a 10.6-point decline in the Hamilton Anxiety Scale score, whereas the placebo group showed an 8.9-point declineStatistically significant advantage for Sympathyl compared with placebo, but size of difference (1.7 scale points) very small
RCT of passionflower versus oxazepam (Serax; brand no longer available in the United States) in GADEach group had 18 patients with GAD23; both groups started with mean Hamilton Anxiety Scale scores of 20 and ended with significant reductions to 6; the groups also had the same level of side effectsBoth groups equally positive but small study with no placebo group; results unclear