Unexpected anaphylaxis to tranexamic acid confirmed by drug provocation testing in orthopedic surgery: A case report.

Tranexamic acid (TXA) is commonly used in orthopedic surgery to reduce perioperative bleeding. Although generally safe, TXA has been associated with rare, but potentially life-threatening anaphylactic reactions. We report a case of severe anaphylaxis following intravenous TXA. A 33-year-old male with no known allergies developed severe bronchospasm, hypotension, ventricular arrhythmias, and lip swelling within min of TXA administration. Initial treatment included oxygen, intratracheal salbutamol, and intravenous pheniramine with delayed epinephrine due to the transient arrhythmias. Serum tryptase measured two hours later was within normal range. Six weeks postoperatively, skin prick test (SPT) showed trace positivity to TXA and a stepwise intravenous drug provocation test (DPT) reproduced clinical symptoms at 100 mg, confirming IgE-mediated hypersensitivity. This case highlights the diagnostic challenges of perioperative anaphylaxis under general anaesthesia and emphasizes the importance of early recognition, prompt epinephrine use, and confirmatory testing for safe perioperative management.