Haloperidol is a typical butyrophenone type antipsychotic that exhibits high affinity dopamine D 2 receptor antagonism and slow receptor dissociation kinetics.  It has effects similar to the phenothiazines .  The drug binds preferentially to D 2 and α 1 receptors at low dose (ED 50 = and mg/kg, respectively), and 5-HT 2 receptors at a higher dose (ED 50 = mg/kg). Given that antagonism of D 2 receptors is more beneficial on the positive symptoms of schizophrenia and antagonism of 5-HT 2 receptors on the negative symptoms, this characteristic underlies haloperidol's greater effect on delusions, hallucinations and other manifestations of psychosis.  Haloperidol's negligible affinity for histamine H 1 receptors and muscarinic M 1 acetylcholine receptors yields an antipsychotic with a lower incidence of sedation, weight gain, and orthostatic hypotension though having higher rates of treatment emergent extrapyramidal symptoms .
Haloperidol is used to treat a wide variety of mental illnesses. Aside from being used as a medication for schizophrenia, haloperidol is used to control acute psychosis, including psychosis induced by drugs such as LSD, amphetamines, ketamine, psilocybin and phencyclidine. It can help control the psychosis associated with high fever or metabolic disease and can reduce the agitation and confusion associated with cerebral sclerosis. Other uses include an adjunctive treatment in alcohol and opioid withdrawal and a treatment for some neurological disorders such as tics and Tourette syndrome. Chronic pain, severe hiccups and severe nausea and vomiting can also be relieved using haloperidol.