Criterion Value of Atypical Drug Responses in the Diagnosis of Atypical Psychiatric Disorders

Abstract

This review provides evidence supporting the notion that the study of atypical pharmacological responses in the treatment of psychiatric disorders may yield useful information about the etiology, taxonomy, and treatment of the atypical disorders. This is based on the assumption that the occurrence of an atypical drug response may reveal distinct underlying mechanisms whose specificity may also be relevant to defining the atypical nature of the disorder. An atypical drug response is defined as unusual and unpredictable effect of a drug, of whatever intensity and irrespective of dosage, which, however, is not a consequence of drug allergy. Such responses have been variously labeled "unusual effects," "idiosyncratic" or "pathological" reactions, "para-reactions," or "paradoxical reactions." They are the outcome of factors associated with different effects of drugs in relation to the variability of ther organic substrate on which they interact or on the variability of the psychic apparatus in the drug-personality interaction.