Zomepirac, dihydrocodeine and placebo compared in postoperative pain after day-case surgery. The relationship between the effects of single and multiple doses.

Zomepirac 100 mg and dihydrocodeine 30 mg were compared with placebo in a controlled randomized, double-blind, single-dose postoperative study. Patients continued to receive either zomepirac or dihydrocodeine for pain relief for 5 days at home in a double-blind study, being allowed to titrate the consumption of tablets to their degree of pain. The efficacy and side effects of the medication were evaluated. In the single-dose phase, both active treatments were significantly better than placebo. In the multiple dosing phase, zomepirac was statistically better than dihydrocodeine. Non-parametric statistical tests indicated highly significant correlations between single- and multiple-dose analgesic measurements for both zomepirac and dihydrocodeine.