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Background and Objective: Pain after tonsillectomy is one of the most common complications. This study was done to compare the effect of Gabapentin and promethazine as premedication to reduce pain after tonsillectomy.
Methods: This clinical trial study was performed on 104 patients aged 7-15 years who were candidate for tonsillectomy. Patients were randomly divided into gabapentin and promethazine groups. The first group received oral gabapentin 20 mg/kg/bw, and the second group was treated with promethazine syrup 0.5 mg/kg/bw one hour before anesthesia. Pain score was recorded based on the MOPS index and recorded and compared during 3, 6, 12, and 24 hours after surgery.
Results: The mean±SD of pain severity in the intervention group with promethazine at 3, 6, 12 and 24 hours after surgery were 1.35±0.84, 0.9±0.87, 0.25±0.52, 0.04±0.19, respectively. Pain severity was 1.58±0.98, 1.13±0.91, 0.69±0.27, and 0.06±0.24 in gabapentin group, respectively. There was no significant difference between pain score of two groups in 3, 6, 12 and 24 hours after surgery.
Conclusion: Gabapentin and promethazine as premedication have a similar analgesic effect in patients after tonsillectomy.