The mechanism of action of first-generation neuroleptics (haloperidol)
Neuroleptic, or antipsychotic, agents are a group of drugs used to treat schizophrenia and other types of psychoses. Haloperidol an older ‘typical’, or ‘first-generation’, neuroleptic is non-selective and binds to a broad range of receptors. It can bind to dopamine D1 and D2, 5-HT2, histamine H1 and α2 adrenergic receptors in the brain. The efficacy of neuroleptics is thought to be due to antagonism of dopamine receptors in the mesolimbic and mesofrontal systems. The adverse effects of typical neuroleptics include tachycardia, impotence and dizziness, and these unwanted effects are caused by non-selective interaction at the α adrenoreceptor. Other adverse effects include and sedation and weight gain, which is due to histamine H1 receptor blockade.
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