Haloperidol is a typical butyrophenone type antipsychotic that exhibits high affinity dopamine D 2 receptor antagonism and slow receptor dissociation kinetics. [42] It has effects similar to the phenothiazines . [17] 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. [43] 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 .

The influence of renal impairment on the pharmacokinetics of haloperidol has not been evaluated. About one-third of a haloperidol dose is excreted in urine, mostly as metabolites. Less than 3% of administered haloperidol is eliminated unchanged in the urine. Haloperidol metabolites are not considered to make a significant contribution to its activity, although for the reduced metabolite of haloperidol, back-conversion to haloperidol cannot be fully ruled out. Even though impairment of renal function is not expected to affect haloperidol elimination to a clinically relevant extent, caution is advised in patients with renal impairment, and especially those with severe impairment, due to the long half-life of haloperidol and its reduced metabolite, and the possibility of accumulation (see section ).

My mom has been a heavy drinker for years, she was sober for about 3 months, then off and on drinking from there. She would drink about 4-5 strong hard alcohol drinks a day. when she finally decided to quit on Saturday, she started getting her worst nightmare. delirium tremors. It started slow, she knew her surroundings, she just was seeing and hearing things she knew was not there. we took her to the hospital, where she is being carefully monitored, and given medication to help. Now visiting my mom… she doesn’t know who we are, or her surroundings at all. she is now on day 7. when will the delusional stage stop? i know the whole process takes months, but is this normal?