Anaphylaxis is an acute onset, potentially fatal systemic allergic reaction. Multiple agents can cause anaphylaxis in the perioperative setting. Ketorolac is a potent analgesic drug and has been widely used for postoperative pain control. A 38-year-old male patient, who had surgery under general anesthesia without any problems, was scheduled for a spinal fusion. There were no problems during anesthesia. In post anesthetic care unit, he was given 30 mg of ketorolac intravenously. After the ketorolac injection, severe hypotension and tachycardia developed and delayed skin rash and wheel appeared. The patient was given epinephrine, antihistamine and steroid. The patient recovered without any significant complications.