Tramadol has a safer profile compared to opioids due to its lower potential of respiratory depression and, therefore, is increasingly used for treatment of postoperative pain. This case report presents massive angioedema following tramadol administration in a female patient who was operated due to arteriovenous malformation and subarachnoid hemorrhage. Our patient was transferred to the intensive care unit (ICU) after five hours of operation for neurologic follow up. Due to postoperative pain, 25 mg of tramadol was injected via an intravenous line and 30 minutes later, the patient started to have difficulty in speaking, swollen tongue, tachypnea and shortness of breath. The tongue swelled massively within minutes and protruded 4-5 cm out of oral cavity. She was diagnosed as massive angioedema; and, 250 mg methyl prednisolone, 8 mg dexamethasone and 45.5 mg pheniramine was administered intravenously. Edema of the tongue subsided following anti-allergic therapy and disappeared 48 hours later. This case indicates that, although considered to be a safe opioid, tramadol may cause life threatening allergic reactions such as massive angioedema.
Keywords: Tramadol, allergy, angioedema