[Double-blind clinical trial of tramadol capsules. First communication: Comparison with pentazocine and placebo (author's transl)].

A new administration form of tramadol (50 mg) was compared in a multicenter double-blind trial with pentazocine (50 mg) and with placebo in patients with acute pains. Each patient received a test preparation once. The preparations were available in identical capsules. During the five-hour observation period the effect on the intensity of pain was recorded with reference to a scale and the undesirable side effects noted. Tramadol was shown to have an analgesic effect about equal to that of the comparative preparation. Both analgesics were superior in effect to the placebo, as was expected. The incidence of side effects from tramadol was less than that with the comparative substance, even if both analgesics had a higher incidence of side effects than the placebo. The results confirm earlier experience obtained with parenteral application of tramadol.