Evaluation of preemptive analgesia with dextromethorphan gargling in patients undergoing tonsillectomy

Background: this double-blind clinical trial was done to attenuate post tonsillectomy pain with preoperative dextromethorphan gargling. methods: in a clinical trial study, sixty patients who were candidate for elective surgery under general anesthesia were randomly divided into three groups. group od (oral dextromethorphan) received 45 mg oral dextromethorphan tablet. group gd (gargling dextromethorphan) were asked to gargle 45 mg dextromethorphan syrup and group pb (placebo) received placebo tablet preoperatively. pain-free period (pfp) and severity of pain at rest and swallowing saliva were recorded. need for additional analgesic and satisfaction after 24 hours were compared between groups. results: three groups were similar in age, weigh and sex (p > 0.05). the pfp was longer in od and gd groups than placebo group (p = 0.002). the severity of pain during swallowing saliva was lower in od and gd groups than placebo group (p = 0.047). the mean dosage of additional analgesic was more in placebo group than od and gd groups (p = 0.005). the median satisfaction after 24 hours was higher in od and gd groups than placebo group (p = 0.048). conclusions: preemptive analgesia by eating or gargling dextromethorphan can effectively attenuate postoperative tonsillectomy pain.