Neuroleptics


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Neuroleptics

 

(also called neuroplegics, antipsychotics, major tranquilizers), a group of pharmacologically active substances that exert a unique depressive influence on many functions of the nervous system.

Neuroleptics are sedatives that effect an indifferent attitude in the patient toward the surroundings, a decrease in motor activity and in skeletal muscle tonus, a weakening of autonomic reactivity (which tends to be accompanied by a decrease in body temperature), a lowering of arterial blood pressure, and a weakening of reflexes from the internal organs. Neuroleptics intensify the action of narcotics, somnifacients, analgesics, and anesthetics, and they weaken the action of stimulators of nervous activity, such as caffeine and phenamine. Neuroleptic substances also have antiemetic properties.

As a result of the influence of neuroleptics on the central nervous system, changes in mental activity and emotional state arise without disturbances of consciousness. These changes are accompanied by fluctuations in the electrical biopotentials of the brain. The antipsychotic action, which is especially characteristic of neuroleptics, accounts for the successful treatment of psychomotor excitement and mental disorders, such as delirium, hallucination, or anxiety. The first neuroleptic, chlorpromazine, was studied by the French pharmacologist F. Courvoisier in the early 1950’s; somewhat later, reserpine was introduced into therapy as a neuroleptic.

Structurally, neuroleptics belong to various classes of chemical compounds; of the greatest practical importance are the derivatives of phenothiazine, thioxanthene, butyrophenone, and indole. Although the mechanism of action has not been sufficiently studied, it is known that neuroleptics influence the transmission of nerve impulses within the synapses of various brain structures. It is also known that neuroleptics suppress the activating influence of the reticular formation of the brain on the cerebral cortex and lower the activity of mediator substances (chemical transmitters), which brings about a change in the functional activity of the brain.

Neuroleptics opened up a new era in the treatment of various mental diseases, for example, schizophrenia and manic-depressive psychosis; they have also been widely used in combination with narcotics and analgesics to eliminate pain during surgery. Neuroleptics have broad application to the clinical practice of internal medicine, especially in the treatment of hypertension, ulcers, and ischemic diseases of the heart; they are also used against itching in skin diseases and as antiemetics in pernicious vomiting of pregnancy.

REFERENCES

Avrutskii, G. Ia. Sovremennye psikhotropnye sredstva i ikh primenenie ν lechenii shizofrenii. Moscow, 1964.
Zakusov, V. V. “Novye psikhofarmakologicheskie sredstva.” Farmakologiia i toksikologiia, 1964, vol. 27, no. 1.
Mashkovskii, M. D. Lekarstvennye sredstva, 7th ed., part 1. Moscow, 1972.
Raiskii, V. A. Psikhofarmakologicheskie sredstva ν meditsinskoi praktike. Moscow, 1972.

V. V. ZAKUSOV

References in periodicals archive ?
The condition is said to typically develop over a period of 24 to 72 hours and can be precipitated not only by starting neuroleptic medications but also after abruptly stopping them or changing dose.
Neuroleptic malignant syndrome can occur with atypical antipsychotic drugs such as olanzapine, particularly when risk factors are present.
In our case, catatonia was not detected before the patient was admitted to the intensive care unit, so we excluded malignant catatonia, and diagnosed him with atypical NMS induced with multiple neuroleptics.
Arslankoylu AE, Kutuk MO, Okuyaz C, Toros E Neuroleptic malignant syndrome due to risperidone misdiagnosed as status epilepticus.
Neuroleptic induced TD is excluded if signs and symptoms are due to other neurologic disorder that may involve basal ganglia or medical disorder like hyperthyroidism or due to ill-fitted dentures or other medications like levodopa, amphetamines, metoclopramide.
Neuroleptic malignant syndrome: Guidelines for treatment and reinstitution of neuroleptics.
Incidence rates for neuroleptic malignant syndrome (NMS) range from 0.
Prolactin responses to neuroleptics in normal and schizophrenic subjects.
Neuroleptic malignant syndrome (NMS) represents a cluster of adverse effects of antipsychotic medications including: hypertonicity, autonomic instability, fever, and cognitive disturbance.
They then gave the rats one of two atypical neuroleptics and found that in both cases the drug severely depressed the response from the CNiFERs.
Other possibilities are atypical neuroleptics such as risperidone and one of the older medicines such as haloperidol, in low doses.