To compare the analgesic effects of intravenous (IV) ketamine with IV ketorolac in acute renal colic . This is a randomized double blind clinical trial and all patient who come to emergency department with acute renal colic ( diagnosed by past history and clinical sign) and signed inform consent form and have not exclusion criteria of the study( unwilling to study participation, drug allergy and ets) , include to the trial. The study population is 126 patients . With block randomization each patients allocated to one of two groups. Group 1, receive 0.6 mg/kg intravenous ketamine as analgesic group2, receive 30 mg intravenous ketorolac as analgesic. All patients will undergo pain intensity measurement by Numeric Rating Scale (NRS) from 0 to 10. At the beginning of study and after 5,15,30,60 and 120 min of intervention we calculate pain level of patients with using of Numeric Rating Scale. We use 0.1 mg/kg morphin sulfat as rescue analgesic if persistent pain . The reduction in Numeric Rating Scale of pain and complications at 0, 5, 15, 30 , 60 , 120 minute and need for rescue analgesia will be recorded and the difference between these values will be evaluated by statistical methods.