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

To investigate efficacy and safety of St. John's wort (SJW) LI 160 in somatoform disorders.

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.

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.

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.