High-potency first-generation antipsychotic (butyrophenone)REQUIRES MONITORINGNARROW THERAPEUTIC INDEX

Haloperidol

Haldol · Haldol Depot

The most widely used dopamine antagonist in acute agitation and delirium in Swedish emergency departments and wards, with rapid onset and minimal anticholinergic burden. The drug has two entirely different dosing worlds: a few milligrams in acute psychotic agitation in younger patients, and tenths of a milligram in delirium in the elderly, where the lowest effective dose for the shortest possible time is the whole principle. What governs safety is the QT interval and extrapyramidal adverse effects.

BOXED WARNING

Dose-dependent QT prolongation with risk of torsades de pointes — obtain an ECG before treatment, and continuous ECG monitoring during intravenous administration. Neuroleptic malignant syndrome with hyperthermia, muscle rigidity, autonomic instability, and rising CK is life-threatening and requires immediate discontinuation. In elderly patients with dementia, antipsychotics are associated with increased mortality and stroke.

Dosing in adults

By indicationuppdaterad 2026-08-22

Indication	Regimen	Comment
Acute agitation in psychosis, adult	2,5–5 mg im, may be repeated after 30–60 minutes	maximum 20 mg per day of all formulations combined
Acute agitation, intravenous	2,5–5 mg iv slowly, repeat as needed	requires continuous ECG monitoring
Delirium in the elderly	0,5–1 mg orally or im, may be repeated	usually no more than 2–3 mg per day
Delirium, oral continuation	0,5–2 mg 1–2 times daily	reassess daily and discontinue as soon as the confusion resolves
Schizophrenia, maintenance treatment	2–10 mg daily orally	specialist treatment; lowest effective dose

Renal impairment

No established dose adjustment, but caution and a lower starting dose in severe renal impairment as the metabolites are excreted renally.

Hepatic impairment

Halved starting dose and slow uptitration in hepatic impairment; metabolism is entirely hepatic and elimination is delayed.

Children

Used rarely and only on a child and adolescent psychiatry indication. Doses in children and adolescents are in the range of tenths to a few milligrams per day, divided into several doses. Dosing should follow the summary of product characteristics and be agreed with a child and adolescent psychiatrist. ECG before initiation.

Pitfall

Contraindicated in Parkinson's disease and dementia with Lewy bodies — dopamine blockade can cause severe rigidity, immobility, and neuroleptic sensitivity reaction. For agitation in these patients, clozapine or low-dose quetiapine is used instead. Also avoid in known long QT syndrome and after recent myocardial infarction, and taper slowly after prolonged treatment to avoid rebound symptoms and dyskinesias.

Pharmacokinetics

BIOAVAIL.: 60–70 % orally
ONSET: minutes iv · 20–40 minutes im · hours orally
t½: approximately 24 hours (14–36 hours)
PROTEIN BINDING: approximately 90 %
METABOLISM: CYP3A4 and CYP2D6, and glucuronidation
EXCRETION: Faecal and renal, as metabolites
DEPOT FORMULATION: haloperidol decanoate; steady state after 2–3 months

Adverse effects by frequency

≥ 10 %

Extrapyramidal symptoms with rigidity and tremor, akathisia, sedation, headache

1–10 %

Acute dystonia, hyperprolactinaemia with amenorrhoea and gynaecomastia, orthostatic hypotension, constipation, weight gain

< 1 %

Torsades de pointes, neuroleptic malignant syndrome, tardive dyskinesia, seizures, agranulocytosis

Monitoring schedule

ECG with QTc: before initiation; continuously during intravenous administration
Potassium and magnesium: before starting and with repeated dosing
Extrapyramidal symptoms and akathisia: daily during ongoing treatment
Temperature and CK with rigidity: immediately on suspicion of neuroleptic malignant syndrome

Interaction burden

32clinically significant

5 contraindicated · 14 major · 13 moderate. Contraindicated with other QT-prolonging drugs, including class IA and III antiarrhythmics, high-dose citalopram and escitalopram, and in untreated hypokalaemia. CYP3A4 inhibitors such as ketoconazole and protease inhibitors raise the concentration; carbamazepine and rifampicin lower it. Additive sedation with benzodiazepines and opioids.

Formulation & cost

Injection solution (Haldol): 5 mg/ml, 1 ml ampoule
Tablet and oral solution: tablet 1, 2 and 4 mg; solution 2 mg/ml
Restriction: none — approved; depot formulation for specialist use