What was the first phenothiazine used for managing psychotic behavior?

Chlorpromazine hydrochloride was the first phenothiazine introduced for managing psychotic behavior. It was developed in the early 1950s and marked a significant breakthrough in psychiatric treatment, being the first antipsychotic medication used to treat schizophrenia and other severe mental disorders. Chlorpromazine works by blocking dopamine receptors in the brain, which helps to reduce symptoms such as delusions and hallucinations.

The introduction of chlorpromazine revolutionized psychopharmacology and paved the way for the development of other antipsychotics, leading to more effective management of psychosis and improvement in patients' quality of life. Its use allowed for the deinstitutionalization of many patients, as it provided a means to control symptoms effectively, facilitating a shift toward community-based treatment.

Other medications listed, while also classified as phenothiazines, were developed later and did not have the same historical impact on the treatment of psychotic disorders.