The study was performed in 428 patients, of whom 216 were women. The median age was 36.5 (16-75) years and the median weight 67 (42-118) kg. The complaints were registered on a 10-cm-long linear analogue scale by the patients and the physicians. The patients were given coded identical-appearing tablets of placebo and different doses of trimipramine (Surmontil, Rhône-Poulenc) and randomized into groups A-E. During the 6 weeks of treatment the grades of complaints were reduced to about the half of pretreatment levels. The groups treated with trimipramine (groups A-D) felt significantly more improved than the group receiving placebo (group E). The side effect of tiredness was somewhat more pronounced 1-2 weeks after start with 50 mg trimipramine in the evening than in the groups receiving placebo and lower dose schedules of trimipramine.