Tranexamic Acid: An Exceedingly Rare Cause of Anaphylaxisduring Anaesthesia

Tranexamic acid (TXA) allergy is extremely rare. An 80-year-old woman without prior exposure to TXA underwent electiveknee replacement. Shortly after induction of anaesthesia and intravenous TXA, she developed hypotension, tachycardia, and facialerythema accompanied by a raised serum tryptase. Later, skin prick and intradermal testing confirmed positive responses to TXAin high dilution and with negative results to the other drugs used. While neuromuscular blocking agents, opiates, and antibioticsremain the most frequent cause of anaphylaxis during anaesthesia, allergy to TXA should always be borne in mind and requiresskin testing for confirmation as there are presently no blood tests available.