Haloperidol Injectable: Dosing and Precautions

Therapeutic action

Antipsychotic.

Indications

• Acute confusional state (delirium) and acute alcohol intoxication.
• Agitation or aggressive behaviour in patients with acute or chronic psychosis, in combination with promethazine.

Forms and strengths, route of administration

• 5 mg in 1 ml ampoule, 5 mg/ml, for IM injection.

Dose and duration

Change to oral treatment as soon as possible. Reduce the dose by half in older patients, maximum 5 mg daily.

Contra-indications, adverse effects, precautions

Due to the numerous and potentially severe adverse effects of haloperidol, patients should be kept under close surveillance.

• Do not administer to patients with cardiac disorders, dementia, Parkinson's disease, or history of neuroleptic malignant syndrome.
• Administer with caution and carefully monitor use in older patients and patients with hypokalaemia, hypotension, hyperthyroidism, renal or hepatic impairment, or history of seizures.
• May cause drowsiness, extrapyramidal syndrome, dyskinesia, anticholinergic effects, sexual dysfunction, QT prolongation, ventricular arrhythmia, orthostatic hypotension, and rarely neuroleptic malignant syndrome.
• Avoid or monitor combination with central nervous system depressants, fluoxetine, paroxetine, sertraline, ritonavir, carbamazepine, rifampicin, phenobarbital, phenytoin, antihypertensive drugs, and drugs that prolong the QT interval.
• Keep the patient in the supine position for 30 minutes after injection because of the risk of orthostatic hypotension.
• Pregnancy: re-evaluate whether treatment is still necessary; if continued, administer at the lowest effective dose and observe the neonate if exposed in the third trimester.
• Breast-feeding: if absolutely necessary, do not exceed 10 mg daily.