In a double-blind, double-dummy randomized controlled clinical trial, the onset and duration of the
analgesic effect of
dipyrone, 1 or 2 g, and
diclofenac sodium, 75 mg, by either the i.m. or the i.v. route were compared in 293 patients (aged 18-70 years) with
acute renal colic. A level of > or = 50 mm on the 100-mm visual analogue scale was required for inclusion in the study. Patients were randomly allocated to six treatment groups, receiving
dipyrone 1 g i.m.,
dipyrone 1 g i.v.,
dipyrone 2 g i.m.;,
dipyrone 2 g i.v.,
diclofenac sodium 75 mg i.m.; and
diclofenac sodium 75 mg i.v., respectively. Evaluations were performed
at 10, 20, 30, and 60 min and 2, 4, and 6 h
after treatment (time 0). Primary efficacy end points included course of
pain, total
pain, percentage of patients with a
pain improvement of 50% or more at each evaluation time,
pain intensity evaluated by the investigator on a 0-3 scale, and differences in
pain intensity. The
analgesic response was more marked and prolonged among patients receiving
dipyrone 2 g i.m. or
dipyrone 2 g i.v. There were no significant differences between
dipyrone 1 g and
diclofenac sodium 75 mg, by either the i.m. or the i.v. route. All treatment regimens were well tolerated.