Go Idiosyncrasy


Idiosyncrasy is a condition in which there is an unusual (usually violent) reaction to the ingestion of certain substances that do not cause any pathological phenomena in most people. Most often, an attack of idiosyncrasy is caused by food substances ( fish , some berries, eggs), medicines (see Drugs), chemicals (bromine, iodine), pollen of some plants, organic paints, etc. The attack of idiosyncrasy develops soon after the organism causing its substance and is accompanied by swelling of the skin and mucous membranes, eczema , urticaria, runny nose , and in more severe cases of dyspnea, asthmatoid condition and gastrointestinal disorders. The duration of the attack from several hours to several days.

When an episode of idiosyncrasy occurs, the use of antihistamines is recommended, for example, diphenhydramine, pipolfen, suprastin. In the future, contact with substances that may cause idiosyncrasy should be avoided.


Although idiosyncrasy is considered a particular manifestation of allergy (see), it has a number of features that contradict this assumption. So, idiosyncrasy usually appears when the agent first enters the body, that is, without prior sensitization of the body, does not cause subsequent desensitization and often occurs under the influence of non-protein nature of substances and, therefore, does not have antigenic properties. Nevertheless, on this basis it is still not possible to completely eliminate the allergic nature of idiosyncrasy, since it is possible that sensitization to a particular agent can either be obtained from the mother (through the placenta or milk), or can occur during life, but escape attention. .

Idiosyncrasy in pharmacology

Drug idiosyncrasy refers to adverse reactions to drugs that occur in a small proportion of patients and do not have an obvious dependence on the dose or duration of therapy. The liver is a frequent target for toxicity. Most of the generally accepted opinions about the mechanisms of drug idiosyncrasy are based on the hypothesis that the reactions have a metabolic basis, including the polymorphism of the metabolism of the drug, or that they are due to a specific immune response to the drug or its metabolites. However, for very few drugs there is strong evidence for any of these mechanisms. Unstable time and dose relationships that characterize individual reactions to drugs indicate the possibility that an event during therapy makes tissues particularly susceptible to the toxic effects of the drug. For example, inflammations are common in humans, and the results of numerous animal studies show that even a small inflammation can increase the sensitivity of tissues to various toxic chemicals. These observations led to the hypothesis that inflammation during drug therapy may reduce the toxicity threshold of the drug and, thus, make a person susceptible to a toxic reaction that would otherwise not have manifested (for example, an idiosyncratic reaction). This hypothesis may explain the features of drug idiosyncrasy using fundamental pharmacological principles, and the results of recent animal studies confirm this. There are still some knowledge gaps that need to be filled to confirm this hypothesis.