Is Idiosyncrasy Genetic?

Is Idiosyncrasy Genetic? Idiosyncratic adverse drug reactions are unpredictable and thought to have an underlying genetic etiology. What is metabolic idiosyncrasy? Drugs that cause IDILI with evidence of an immune response, such as halothane, are classed as immune idiosyncrasy, whereas those without obvious signs of an immune response have been classed as metabolic idiosyncrasy (Zimmerman,