Treatment of somatoform disorders with St. John's wort: A randomized, double-blind and placebo-controlled trial

Objective: To investigate efficacy and safety of St. John's wort (SJW) LI 160 in somatoform disorders. Methods: In a prospective, randomized, placebo-controlled, and double-blind parallel group study, 184 outpatients with somatization disorder (ICD-10 F45.0), undifferentiated somatoform disorder (F45.1), and somatoform autonomic dysfunction (F45.3), but not major depression, received either 300 mg of SJW extract LI 160 twice daily or matching placebo for 6 weeks. Six outcome measures were evaluated as a combined measure by means of the Wei Lachin test: Somatoform Disorders Screening Instrument-7 days (SOMS-7), somatic subscore of the HAMA, somatic subscore of the SCL-90-R, subscores "improvement" and "efficacy" of the CGI, and the global judgment of efficacy by the patient. Results: In the intention to treat population (N=173), for each of the six primary efficacy measures as well as for the combined test, statistically significant medium to large-sized superiority of SJW treatment over placebo was demonstrated (p<.0001). Of the SJW patients, 45.4% were classified as responders compared with 20.9% with placebo (p=.0006). Tolerability of SJW treatment was equivalent to placebo. Conclusions: Administration of 600 mg of SJW extract LI 160 daily is effective and safe in the treatment of somatoform disorders, thereby confirming results from a previous study.