IRCT201208138075N3 IRCT 2012-12-23 Vice chancellor for research, Tehran University of Medical Sciences Effects of acetaminophen on post tonsillectomy pain Effects of intravenous Acetaminophen versus intravenous Dexamethasone on post tonsillectomy pain in children between 1 and 12 years old. 2012-08-31 anticipated 84 Complete https://irct.ir/trial/8492 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Other design features: In the recovery room, syringe 10 cc medication was ready by a nurse and were labeled A and B. One of which contains 15 mg of intravenous acetaminophen in one cc and the other, 0.1 mg Dexamethasone in one cc. Intravenous acetaminophen brand apotel UNI PHARMA Manufacturing Plant in Greece and brand Dexamethasone is( Iran) Osvah Decadrol construction. At half an hour to the end of tonsillectomy, based on block randomization table 1 cc of A or B for each kilogram of body weight is injected slowly and only once. 3 Hypertrophy of tonsils. Intervention 1: In group 1: 15mg/kg iv acetaminophen will be administrated at 30 min before the end of the surgery. Intervention 2: In group 2: 0.1 mg/kg iv dexamethasone will be administrated at 30 min before the end of the surgery.