Dopamine antipsychotic drugs affecting

The first generation antipsychotics, now known as typical drugs, were all D2 receptor blockers and, as such, very likely to produce Parkinsonian side effects. Because antipsychotic potency was associated with D2 receptor affinity, it was assumed that dopamine overactivity was the essential defect in schizophrenia and that a direct dopamine blockade was the definitive route to treatment. But these drugs affected both the target dopamine pathways of the mesolimbic projection and the uninvolved nigrostriatal projection. Unfortunately, that meant that movement disorders were the price that had to be paid for antipsychosis. 

Consequently, antipsychotic drugs all share a basic mechanism of action that involves dopamine receptor blockade. It is apparent, however, that they are not all equal in their ability to affect specific sub-types of dopamine receptors, and that their effectiveness and side effects are related to their affinity and preference for certain receptors. As indicated earlier, other neurotransmitters may also be involved in the pathogenesis of psychosis, and differences in specific antipsychotic medications may be related to their ability to directly or indirectly affect these other transmitters as well as block dopamine influence. Future studies will continue to clarify how current antipsychotics exert their beneficial effects and how new agents can be developed to be more selective in their effects on dopamine and other neurotransmitter pathways. 

Antipsychotic drugs A major classification of drugs, most of which are dopamine receptor antagonists (with the exception of the newer antipsychotic medications), and are used to address disturbances in affect and mood such as psychosis, delusions, and psychotic depression. 

Reserpine, used as a folk medicine in India, was found to have antipsychotic properties at about the same time as CPZ. Both agents affected the dopaminergic system, albeit in different ways, but the functional results were similar (i.e., lowering dopamine activity). This phenomenon has continued to be an important factor in hypotheses about the mechanism of action of these drugs and for biological theories about the pathophysiology of psychotic disorders. 

Numerous other drugs have a myotoxic effect by various mechanisms, including antipsychotic and antidepressant drugs (e.g., olanzapine, clozapine) and drugs of abuse (e.g., cocaine, heroin, methamphetamine) that affect CNS and muscle dopamine and serotonin receptors fluoroquinolones glucocorticoids ... 

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