DEXTROMETHORPHAN AND PAIN AFTER TOTAL ABDOMINAL HYSTERECTOMY

Dextromethorphan is an N-methyl-D-aspartate (NMDA) receptor antagonist which has been shown to inhibit the development of cutaneous secondar y hyperalgesia after tissue trauma. We studied 60 ASA I-II patients un dergoing total abdominal hysterectomy in a randomized, double-blind, p lacebo-controlled study. Patients received either dextromethorphan 27 mg capsules, two doses before operation and three doses in the first 2 4 h after operation, or placebo. Visual analogue pain scores (VAS) at 24 and 48 h were assessed at rest, on coughing and on sitting up, and were not significantly different between groups. Morphine consumption from a patient-controlled analgesia (PCA) device was also not signific antly different between groups. Evidence of secondary hyperalgesia was assessed with von Prey hairs 10 cm above the Pfannenstiel incision. B oth groups of patients exhibited evidence of secondary hyperalgesia af ter 24 and 48 h but there were no significant differences between grou ps. There was also no difference between groups in VAS scores at 1 mon th.