Allergic drug reactions: identification and management.

Any attempt to distinguish allergic drug reactions from other adverse drug reactions (ADRs) can be complicated by the fact that terminology in this area has not been standardized. True allergic reactions are those resulting from immunologic causes, and their prevalence is only 6 to 10% of all ADRs. A number of factors predispose individuals to drug allergies--the recognition of which might aid the healthcare professional in diagnosing these reactions--and other criteria can be helpful in the process. In order to successfully separate pseudoallergic from allergic from other adverse drug reactions, the clinician must proceed with caution and suspicion. When foreseeable allergic reactions cannot be prevented, measures can be taken that might reduce their impact.