Premedication with oral Dextromethorphan reduces intra-operative Morphine requirement

Intra-operative pain has adverse effects on hemodynamic parameters. due to complications of opioidsfor pain relief, using non-opioids medication is preferred . the purpose of this study was to investigate the effect of oraldextrometorphan premedication on intra-operative morphine requirement.methods: after approval of the ethics committee and informed consent, 40 adult patients who stand in american societyof anesthesiologists physical status i and il, under general anesthesia for elective laparatomy were selected andclassified in two equal groups randomly. in group a, oral dextromethorphan (60mg) was administered at 10 pm and 6am preoperatively . in group b, placebo (dextrose) was administered. after induction of general anesthesia and beforeskin incision, intravenous morphine (0.01 mg/kg) was administered. during surgery, when systolic blood pressure orheart rate was increased more than 20% of the preoperative baseline, 0.01 mg/kg morphine was administered. at theend of surgery, the totally prescribed morphine (mglkg) and maximal increase in systolic, diastolic, mean arterial bloodpressure and heart rate relative to the baseline values were calculated and statistically compared with student's t-test.results: the mean dose of administered morphine during surgery was significantly less in group a than group b(p