Intolerance idiosyncratic reactions

In addition to their action as local anaesthetics, the following actions on other parts of the body are possible. These effects are not clinically significant except in intolerant individuals, those with idiosyncratic reactions, in cases where absorption into the blood stream is unexpectedly rapid or in those with impaired metabolism and/or excretion. 

This class of ADRs includes drug allergies (hypersensitivity reactions), idiosyncratic responses, or intolerance. These types of ADRs are difficult if not impossible to predict and are therefore unavoidable until sufficient knowledge of the drug and the patients taking this drug allows the development of... 

Although immunologic reactions to acetyl salicylic acid (Aspirin, ASA) may occur, anaphylactic-type reactions to ASA are more commonly non-allergic. Often not apparent until adult life, ASA intolerance is probably a genetically determined idiosyncratic response (Schlumberger, 1980). 

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