Neuroleptic drugs, specific agents

Pioneers in the field recognized and wrote about the lobotomy-like effects of the neuroleptic drugs when they first came into use, but in recent years drug advocates have promoted the false impression that these medications have a specific antipsychotic or antischizophrenic effect. In reality, the overriding clinical effect of these highly toxic chemical agents is to render patients and inmates more emotionally flat and indifferent, more apathetic and docile, and less autonomous and self-directed. 

Dopamine receptor blocking agents. Many of the neuroleptics used in the treatment of schizophrenia frequently produce parkinsonian symptoms as unwanted effects. Neuroleptics block dopamine receptors and their therapeutic effect seems to be related to this action. Although these drugs act on DA systems without distinction, some are more selective. Thioridazine, clozapine and molindone, for example, have electrophysiological effects in the limbic region of the brain but little action in the nigro-striatal area. This selectivity may be related to receptor subtype specificity (see Chs 12 and 54). 

Drug treatment with certain agents such as specific types of neuroleptics and reserpine produce PD as a side effect. 

Qll Other neuroleptic agents include phenothiazines, such as chlorpromazine, promazin and thioridazine, and thioxanthines, such as flupenthixol. The non-specific blockade of dopaminergic receptors afforded by these drugs leads to development of side effects, such as endocrine dysfunction and extrapyramidal motor symptoms. The unwanted antagonism of motor tracts results in extrapyramidal side effects, such as Parkinsonism and tardive dyskinesia. The latter is associated with involuntary movements of the face, limbs and trunk. Chronic neuroleptic therapy can inhibit the release of GABA. This in turn leads to changes in mobility. 

Arrhythmias have been reported following the use of neuroleptic agents but are not specific to liver disease. However, there may be a greater risk in patients with hepatic impairment owing to accumulation of the drug. 

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