Effect of Cimetidine antinociception on post operative pain and comparison with morphine

Introduction: pain is the most common complaint of patients and its treatment is the most ancient problem of human being . Opioids have many side effects that have limited morphine administration . Recent studies have shown that cimetidine (CIM) induce antinociception after IP in mice . this study was designed to evaluate antinoception of CIM to control post operative pain in compare with morphine ( MOR) . Materials and Methods : this study was a double blind clinical trial .9o patients( male & female) after earning satisfaction were divided to three groups : A) CIM (5mg /kg ) B) MOR( 0/1 mg/kg) c)CIM+ MOR .Drugs were injected (by slowly IV ) after peaking of pain in the post operative . pain mark and analgesic time were evaluated by methods Numeric Rating Pain Scale (RPS) after 0/5 h and each 1h from injecting. Results:Confounding variables for example age , sex , type of anesthesia and surgery in this study were not significant effect on antinociception (P>0/05 ) . pain mark at half an hour and 1h after njection was not significant in three groups (P>0/05 ) but was significant compared with before injection(P=0/00 ).Also,analgesic time was not significant in three groups (P=0/784 ). Conclusion: Cimetidine antinociception (time and quality) is analogous with morphtion.