IRCT2013052311067N2 IRCT 2013-07-20 Vice chancellor for research, Tabriz University of Medical Sciences Comparison of injection form of acetaminophen with morphine Randomized clinical trial comparing intravenous Acetaminophen with Morphine on pain and peritoneal irritation signs in patients with acute surgical abdomen 2013-03-21 anticipated 120 Complete https://irct.ir/trial/11416 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Other design features: For randomizing patients into two groups, we used pocket method. Numbers from 1 to 120 were put in some pockets which were similar in size and color and were shuffled. While including a patient in the study one pocket was chosen randomly. If the figure was in range of 1 to 60, patient was placed in acetaminophen group and if it was in range of 61 to 120 patient was placed in morphine group. We used a double blinded study to prevent research outcomes from being influenced by the placebo effect or observer bias. In this study, neither the emergency physician nor the patient knew about the administered drug (morphine or acetaminophen). 2-3 Abdominal pain and tenderness. Intervention 1: In acetaminophen group, one shot of intravenous acetaminophen (trade name: Apotel) will be injected with a dose of 15 mg/kg intravenously. Intervention 2: In morphine group, one shot of morphine (trade name: MS) will be injected with a dose of 0.1 mg/kg intravenously.