Pinoxepin (INNTooltip International Nonproprietary Name; developmental code name P-5227; pinoxepin hydrochloride (USANTooltip United States Adopted Name)) is an antipsychotic of the tricyclic group with a dibenzoxepin ring system which was developed in the 1960s but was never marketed. It was found in clinical trials to have effectiveness in the treatment of schizophrenia similar to that of chlorpromazine and thioridazine. The drug has marked sedative effects but causes relatively mild extrapyramidal symptoms.