Abstract A 72-year-old male patient was scheduled for coronary artery bypass graft surgery because of severe three-vessel disease. Induction of anaesthesia was uneventful. Following bolus infusion of tranexamic acid (Exacyl ®), the patient presented clinical signs consistent with anaphylactic shock. Surgery was postponed and the patient recovered without sequaelae. Allergological investigations (cutaneous tests, serum IgE concentrations, in vitro histamine-release tests) suggest that this is the first reported case of anaphylactic shock to tranexamic acid. Several weeks later, the patient underwent surgery with a similar anaesthetic regimen and the clinical course was uneventful.