Tachyphylaxis: What is it? When and how does it manifest? Features and Causes

, in order to obtain the therapeutic effect again, it may seem obvious to increase the dosage of the drug administered. However, such a practice is not always possible and, on the contrary, is sometimes contraindicated due to the risk of reaching the toxic dose. although drugs, by definition, are compounds used in therapy for the treatment of disorders and pathologies, taking excessive doses can produce toxic effects, even very serious and sometimes even fatal.

that are the target of the drug (for example, conformational change that hinders the binding with the drug).

Desensitization of the receptor: following the interaction with the drug and the activation of an initial response, the target receptor can undergo desensitization. Generally, in such a situation, the receptor is still able to bind to the drug even if with a lower affinity and with a reduced ability to respond to the stimulus.

Loss of receptors or reduced availability of receptors at the cell membrane level: following continuous exposure to the drug, the so-called receptor down-regulation may occur, with a consequent reduction in the efficacy of the administered drug.