The dosage that haloperidol is administered at depends on several factors including patient age, body weight and the condition for which the drug is being prescribed. Some examples of the dosage schedule for haloperidol are described below.
Single doses of 1 mg to 5 mg can be given either orally or intramuscularly and repeated every 4 to 8 hours. An oral dose of 100 mg per day must not be exceeded. For intravenous administration, single doses of 5 mg to 10 mg can be given but must not exceed 50 mg per day.
Chronic (long-term) conditions
For chronic conditions, the oral daily dose of haloperidol is usually between 0.5 mg and 20 mg. The lowest dose at which the condition can be controlled should be maintained. The dose is therefore started at its lowest and slowly up-titrated until the correct dose is achieved.
In some cases of psychosis that fails to respond to haloperidol, oral doses as high as 300 mg to 500 mg daily have been tried. These experimental doses were usually administered in conjunction with an anticholinergic, antiparkinsonian drug such as Biperiden or Benzatropine. However, these studies led to serious adverse effects such as hypotension and severe cardiac arrhythmia.
Depot forms of haloperidol are also available, which involves the drug being deeply injected into the bodily tissue where it can be slowly released into the body over a period of weeks.
Dosage by disease
The haloperidol doses that are recommended by the FDA for several specific conditions are described below:
- Gilles de la Tourette's syndrome – 0.5 mg to 2 mg for moderate symptoms and 3 to 5 mg for severe symptoms, two to three times daily.
- Psychotic disorders – 0.5 mg to 2 mg for moderate symptoms and 3 mg to 5 mg for severe symptoms, two to three times daily.
- Schizophrenia – 0.5 mg to 2 mg for moderate symptoms and 3 mg to 5 mg for severe symptoms, two to three times daily.
Haloperidol is not approved for use in children under 3 years of age.
For children aged 3 to 12 years, the recommended dose for Gilles de la Tourette's syndrome is 0.05 to 0.075 mg/kg/day orally in two to three divided doses, followed by increases of 0.5 mg at five to seven day intervals, until a therapeutic effect is achieved.
For psychotic disorders and schizophrenia the initial dose should be 0.05 mg/kg/day orally in two to three divided doses, followed by the dosage increase regimen described above.