Evaluation of the efficacy and safety of terguride in patients with fibromyalgia syndrome: results of a twelve-week, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. To assess the efficacy and safety of terguride, a partial dopamine agonist, in patients with fibromyalgia syndrome (FMS). In a 12-week, multicenter, double-blind, placebo-controlled, parallel-group study, 99 patients were randomized at a ratio of 2 to 1 to receive terguride or placebo. Over 21 days, the dosage was titrated to a maximum daily dose of 3 mg of terguride or placebo, and this fixed dosage was continued over 9 weeks. The primary efficacy variable was the intensity of pain (100-mm visual analog scale). Secondary efficacy variables included the Fibromyalgia Impact Questionnaire (FIQ