Somatization disorder (SD) is commonly seen in medical clinics and is associated with significant impairment in functioning as well as excessive utilization of health care. While antidepressants have been studied in some functional somatic syndromes such as fibromyalgia and chronic fatigue, there are no pharmacologic treatment studies of SD itself. In this prospective, 8-week, open-label study, 15 patients diagnosed with either full SD or abridged somatization, by Escobar's criteria (four unexplained physical symptoms for men or six for women), were given nefazodone, titrated to 150 mg bid. The primary outcomes included measures of physical symptom severity (visual analogue scale), functioning (SF-36), and overall improvement (CGI). Fourteen of the 15 patients achieved the target dose of 300 mg/day and completed the trial. 73% of the patients were rated as improved on the CGI, 79% improved on the self-rated visual analogue scale and 73% of the patients improved on the SF-36. There was significant improvement for the whole group (prepost) on the SF-36, as well as on the HAM-D and the HAM-A. Of the nine patients with a categorical depression diagnosis, 55% of them were rated as improved on the CGI, and 67% improved on both the VAS and the SF-36. Of the six nondepressed patients, 67% were rated as improved on the CGI, 83% improved on the SF-36, and 50% improved on the VAS. Adverse events were generally mild and resulted in only one discontinuation. Although these data need to be confirmed in a larger, double-blind, placebo-controlled trial, they suggest that patients with SD will accept and tolerate therapy with nefazodone and that nefazodone may be a useful treatment for these patients.