Anaphylactoid reaction following ketorolac tromethamine administration

To report a case of an anaphylactoid reaction to injectable ketorolac tromethamine in a patient with no prior history of allergies or risk factors associated with nonsteroidal anti-inflammatory drug-induced hypersensitivity reactions.

A 37-year-old man without a significant medical history presented to an emergency department with vague, dull, left-sided chest pain. Myocardial infarction was ruled out based on an unremarkable electrocardiogram, chest X-ray, and laboratory data that were within normal limits. Sublingual nitroglycerin 0.4 mg, magnesium/aluminum hydroxide gel 30 mL, and intravenous ranitidine 50 mg were administered without resolution of symptoms. Ketorolac tromethamine 60 mg was administered intramuscularly with resolution of symptoms. The patient was discharged; however, within 30 minutes, he returned to the emergency department with facial swelling, shortness of breath, and chest tightness. Multiple doses of aerosolized albuterol and intravenous methylprednisolone and diphenhydramine were administered, resulting in a slight improvement of symptoms. The patient was admitted for a complete cardiac evaluation that proved negative. The allergic symptoms resolved and the patient was discharged without medication after a three-day hospitalization.

Ketorolac tromethamine is the first injectable nonsteroidal antiinflammatory drug approved for short-term pain management. A review of the literature revealed no similar cases of anaphylactoid reaction.

Healthcare professionals must be aware of the potential risks of anaphylactoid reactions, especially in light of the increased use of injectable ketorolac in the ambulatory setting and availability of the oral formulation.