Haloperidol

Indications

Haloperidol is used for: Schizophrenia, Delirium, Hiccups, Acute psychosis, Hyperactivity, Aggression, Agitation and confusion, Tic disorders, Tourette syndrome, Chorea, Nausea and vomiting, Dementia.

Adult Dose

Oral Psychoses Adult: 0.5-5 mg bid/tid, may increase up to 100 mg daily in severe or resistant cases. Usual maintenance: 3-10 mg daily. Tourette's syndrome; Severe tics Adult: Initially, 0.5-1.5 mg tid. Up to 30 mg daily may be required in Tourette's syndrome; adjust dose carefully to obtain optimum response; usual maintenance: 4 mg daily. Short-term adjunct in severe anxiety or behavioral disturbances Adult: 0.5 mg bid. Restlessness and confusion Adult: 1-3 mg every 8 hr. Intractable hiccup Adult: 1.5 mg tid, adjust according to response. Intramuscular Acute psychosis Adult: Doses range from 2-10 mg, may be given every hr or at intervals of 4-8 hr, until symptoms are controlled. Max: 18 mg/day. For emergency control of severely disturbed patients: Up to 18 mg may be given IV/IM. Elderly: PO: Lower initial doses and more gradual adjustments recommended; 0.25-0.5 mg PO q8-12hr initially IM (prompt-acting): Lower adult doses and longer dosing intervals recommended compared with typical adult doses

Child Dose

<3 years: Safety and efficacy not established Psychosis/Sedation 3-12 years (15-40 kg): 0.25-0.5 mg/day PO divided q8-12hr initially; may be increased by 0.5 mg/day every 5-7 days PRN; maintenance: 0.05-0.15 mg/kg/day PO divided q8-12hr 6-12 years: Lactate (prompt-acting): 1-3 mg IM q4-8hr PRN; not to exceed 0.15 mg/kg/day >12 years: Moderate disease, 0.5-2 mg PO q8-12hr initially; severe disease, 3-5 mg PO q8-12hr; not to exceed 30 mg/day Tourette Disorder 3-12 years: 0.5 mg/day PO initially; dose increased by 0.5 mg every 5-7 days until therapeutic effect achieved, then reduced to lowest effective maintenance level of 0.05-0.075 mg/kg/day PO divided q8-12hr >12 years: 0.5-2 mg PO q8-12hr initially; if severe symptoms necessitate increased dosage, titrate upward to 3-5 mg PO q8-12hr; if patient remains inadequately controlled, daily doses up to 100 mg have been used (safety not determined) Behavioral Disorders 3-12 years: 0.5 mg/day PO initially; dose increased PRN by 0.5 mg every 5-7 days until therapeutic effect achieved, then reduced to lowest effective maintenance level of 0.05-0.075 mg/kg/day PO divided q8-12hr Acute Agitation <12 years: Safety and efficacy not established >12 years: 0.5-3 mg PO, repeated in 1 hour PRN; alternatively, 2-5 mg IM, repeated in 1 hr PRN

Renal Dose

Administration

May be taken with or without food. May be taken w/ meals to minimise GI irritation.

Contra Indications

Severe toxic CNS depression; preexisting coma; Parkinson's disease; lactation.

Precautions

Parkinsonism; epilepsy, allergy, angle-closure glaucoma, benign prostatic hyperplasia; severe cardiac or hepatic disease; extremes in temp (hot and cold weather); presence of acute infections or leucopenia; hyperthyroidism; pregnancy, elderly, children. Patients receiving anticoagulants. Discontinue upon signs of neurological toxicity in patients taking haloperidol and lithium. Lactation: Drug enters breast milk; not recommended

Pregnancy-Lactation

Pregnancy There are no well controlled studies in pregnant women; there are reports of cases of limb malformations observed following maternal use with drug along with other drugs which have suspected teratogenic potential during first trimester of pregnancy; causal relationships were not established in these cases; however, such experience does not exclude possibility of fetal damage due to therapy; drug should be used during pregnancy or in women likely to become pregnant only if benefit clearly justifies a potential risk to fetus; infants should not be nursed during drug treatment Neonates exposed to antipsychotic drugs during third trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery; there have been reports of agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, and feeding disorder in these neonates; these complications have varied in severity; while in some cases symptoms have been self-limited, in other cases neonates have required intensive care unit support and prolonged hospitalization Lactation Drug is excreted in human breast milk; infants should not be nursed during drug treatment

Interactions

Carbamazepine and rifampicin reduce plasma concentrations. Symptoms of CNS depression may be enhanced by CNS depressants e.g. alcohol, hypnotics, general anaesthetics, anxiolytics and opioids. May reduce antihypertensive action of guanethidine. May increase risk of arrhythmia when used with drugs that prolong QT interval or diuretics that can cause electrolyte imbalance. May increase plasma levels of haloperidol when used with clozapine or chlorpromazine. Potentially Fatal: Increases lithium blood levels and may predispose to neuroleptic malignant syndrome.

Adverse Effects

Side effects of Haloperidol : Extrapyramidal symptoms Akathisia, Dystonia, Muscle stiffness, Neuroleptic malignant syndrome (NMS; infrequent but serious), Parkinsonism, Tardive dyskinesia Common Anticholinergic effects, Sedation, Weight gain, Erectile dysfunction, Oligomenorrhea or amenorrhea Less common Orthostatic hypotension (after IM injection), tachycardia Agitation, anxiety, cerebral edema, depression, dizziness, euphoria, headache, insomnia, poikilothermia, restlessness, weakness, confusion Anorexia, constipation, dyspepsia, ileus, decreased gag reflex Lens opacities (prolonged use) Uncommon ECG changes, Photosensitivity, Pruritus, Diarrhea, Blood dyscrasia, Ejaculatory disorder, Galactorrhea Rare Seizure, Cholestatic jaundice, Priapism Potentially Fatal: Neuroleptic malignant syndrome

Mechanism of Action

Haloperidol blocks postsynaptic dopamine D1 and D2 receptors in the mesolimbic system and decreases the release of hypothalamic and hypophyseal hormones. It produces calmness and reduces aggressiveness with disappearance of hallucinations and delusions.