The diagnosis of acute anaphylactoid reactions to anaesthetic drugs.

Patients with a presumptive diagnosis of an acute anaphylactoid reaction to anaesthesia were investigated to determine the cause of the reaction and the drug responsible by intradermal testing, patch and prick testing, sequential complement measurement, passive transfer testing and challenge. The most valuable information was provided by intradermal testing and a diagnosis could be made in 150 of 165 patients. When analphylactoid reactions to anaesthetic drugs occur, intradermal testing one month after the reaction and sequential complement measurements in the immediate post reaction period will enable the diagnosis to be established in the majority of cases. Intradermal testing is of no value for trivial reactions or reactions to colloid solutions or contrast media.