Haloperidol

Haloperidol, sold under the brand name Haldol among others, is a typical antipsychotic medication. Haloperidol is used in the treatment of schizophrenia, tics in Tourette syndrome, mania in bipolar disorder, delirium, agitation, acute psychosis, and hallucinations from alcohol withdrawal. It may be used by mouth or injection into a muscle or a vein. Haloperidol typically works within 30 to 60 minutes. A long-acting formulation may be used as an injection every four weeks by people with schizophrenia or related illnesses, who either forget or refuse to take the medication by mouth.

Haloperidol may result in a movement disorder known as tardive dyskinesia which may be permanent. Neuroleptic malignant syndrome and QT interval prolongation may occur, the latter particularly with IV administration. In older people with psychosis due to dementia it results in an increased risk of death. When taken during pregnancy it may result in problems in the infant. It should not be used by people with Parkinson's disease.

Haloperidol was discovered in 1958 by Paul Janssen, prepared as part of a structure-activity relationship investigation into analogs of pethidine (meperidine). It is on the World Health Organization's List of Essential Medicines. It is the most commonly used typical antipsychotic. In 2020, it was the 303rd most commonly prescribed medication in the United States, with more than 1 million prescriptions.