Haldol (Haloperidol)

Haloperidol injectable solution is indicated for short‑term control of severe psychiatric symptoms when rapid onset of action is required.

• Schizophrenia, particularly acute exacerbations requiring rapid symptom control.
• Acute psychotic episodes, including those associated with bipolar disorder or substance‑induced psychosis.
• Manic episodes with marked agitation or psychomotor excitement that do not respond adequately to oral therapy.
• Severe agitation or aggression that poses an immediate risk to the patient or others, often in emergency or inpatient settings.
• Tourette syndrome with disabling motor or vocal tics that have not improved with first‑line treatments.

Haloperidol injectable solution may cause a range of adverse effects, some of which are dose‑dependent and reversible, while others require prompt medical attention.

Common

• Drowsiness or sedation.
• Extrapyramidal symptoms such as tremor, rigidity, or akathisia.
• Dry mouth and constipation.
• Blurred vision or dizziness.
• Orthostatic hypotension or blood pressure changes.
• Weight gain or metabolic changes.

Serious

• Neuroleptic malignant syndrome, a life‑threatening reaction with fever, muscle rigidity, and autonomic instability.
• Tardive dyskinesia, persistent involuntary movements that may be irreversible.
• Cardiac arrhythmias, including QT prolongation, especially in patients with pre‑existing heart disease.
• Severe depression or suicidal thoughts, particularly in patients with mood disorders.

When prescribing haloperidol injectable solution, clinicians should evaluate patient history and monitor for conditions that could increase the risk of adverse outcomes.

• History of cardiovascular disease, especially arrhythmias or prolonged QT interval.
• Pre‑existing movement disorders such as Parkinson’s disease.
• Severe hepatic or renal impairment that may affect drug clearance.
• Pregnancy or breastfeeding status, as safety data are limited.
• Concomitant use of other dopamine‑blocking agents, which can amplify extrapyramidal effects.
• Elderly patients, who may be more sensitive to sedation and orthostatic hypotension.

Haloperidol injectable solution can interact with several medications, altering its efficacy or increasing the likelihood of serious side effects.

Avoid

• Other antipsychotics or dopamine antagonists, which may cause additive extrapyramidal toxicity.
• Medications that prolong the QT interval, such as certain antiarrhythmics, macrolide antibiotics, or antipsychotics.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) that can raise haloperidol plasma levels.

Use with caution

• CYP3A4 inducers (e.g., rifampin, carbamazepine) that may reduce therapeutic effect.
• CNS depressants, including benzodiazepines or opioids, which can enhance sedation.
• Anticholinergic agents, which may mask early signs of extrapyramidal symptoms.