1 Study Guide for Medication Treatment Schizophrenia Spectrum and Other Psychosis Disorders

2 Study Guide for Medication Treatment Schizophrenia Spectrum and Other Psychosis Disorders

3 The FDA indications for Chlorpromazine include the following: Schizophrenia - positive symptoms Bipolar I acute manic type Nausea and vomiting Acute agitation - explosive hyperexcitable behavior Chronic hiccups Adjust treatment of tetanus Acute intermittent porphyria Relief of apprehension before surgery (Mann & Marwaha, 2023). Non-FDA uses Off-label adjust treatment of serotonin syndrome and migraine associated relief of vomiting and nausea (Mann & Marwaha, 2023). Drug classification Chlorpromazinebelongs to the class of drugs referred to as typical antipsychotics, first- generation antipsychotics, or neuroleptic medication category. Typical or first-generation

4 antipsychotics are dopamine receptor antagonists (DRA) first developed in the 1950s (American Psychiatric Association, 2019). Mechanism of action The exact mechanism of action is not yet fully understood; however, it is believed that Chlorpromazineproduces its antipsychotic effect via the post-synaptic blockade of the D2 receptors found in the mesolimbic pathway. At the same time, the blockage of the D2 receptors in the nigrostriatal pathway creates its extrapyramidal side effects. The blockade of dopamine D2, histamine H1, and muscarinic M1 receptors create an antiemetic effect. The drug is extensively metabolized by the liver, kidney, and GI tract (Mann & Marwaha, 2023). It is then excreted in the feces, urine, and bile. Pharmacokinetics The pharmacokinetics ofChlorpromazineis not fully understood as well. More so, it depends on the route of administration and the individual patient. Nonetheless, the kidneys may excrete about 43-65% of the daily dose in 24 hours. 4 of the 5 clinically important metabolites are biologically active (Mann & Marwaha, 2023). A lingering half-life may increase the effects of the medication in the patient. Pharmacodynamics Chlorpromazineis considered a dopamine inhibitor. It stimulates the release of prolactin by inhibiting the prolactin release inhibitory factor. This also increases the turnover of dopamine in the brain. The drug is believed to be having antipruritic, anti-emetic, serotonin-blocking, as well as, antihistaminic properties (Stip et al., 2020). Its ganglion-blocking activity is sligh