SUMMARYPropanidid followed by intravenous atropine and suxamethonium induced anaphylaxis in a 29–year-old woman. The patient had previously been exposed to suxamethonium and atropine but the episode reported here occurred after initial exposure to propanidid. The patient's leucocytes eight weeks after anaesthesia released histamine in vitro in the presence of both propanidid and atropine. Histamine release, however, could not be demonstrated at 17 and 22 weeks after anaesthesia, hence the adverse reaction in this context was transient in nature. The abnormal response to these drugs does not appear to be dependent upon immunological mechanisms, but is in all probability idiosyncratic.