ABSTRACT
As the overall process of anaesthesia has become safer, the relative importance of hypersensitivity or anaphylactic reactions has increased. The incidence of such adverse events to intravenous agents is between 1:5000 and 1:20 000. It is not possible to give a more precise figure because anaesthetic techniques inevitably involve some polypharmacy and the role of other drugs (e.g. neuromuscular blocking agents or colloid infusions) may be difficult to determine. The incidence associated with individual induction agents is given in Table 32.5. Allergic reactions to some other drugs are also included for comparison.
