Haldol (Haloperidol)

Haloperidol (Haldol) is indicated for several psychiatric and neurological conditions where dopamine blockade is therapeutic.

• Schizophrenia, including acute exacerbations and maintenance therapy, where haloperidol helps reduce hallucinations, delusions, and thought disorder.
• Acute psychotic episodes unrelated to schizophrenia, such as drug‑induced or brief psychotic disorder, for short‑term symptom control.
• Manic episodes of bipolar disorder, used as an adjunct to mood stabilizers to lessen elevated mood, hyperactivity, and impulsivity.
• Tourette syndrome and other tic disorders, providing reduction in motor and vocal tics when other treatments are insufficient.
• Severe agitation or aggression requiring rapid control, administered in hospital settings to calm patients safely.

Haloperidol may cause a range of adverse effects, which are generally categorized by frequency and clinical significance.

Common

• Drowsiness or sedation, often most noticeable at treatment initiation.
• Extrapyramidal symptoms such as tremor, rigidity, or akathisia, reflecting dopamine blockade in the basal ganglia.
• Dry mouth and constipation, resulting from anticholinergic effects.
• Blurred vision or ocular discomfort, which may affect near tasks.
• Weight gain or increased appetite, potentially contributing to metabolic changes.
• Nausea or vomiting, usually mild and transient.
• Orthostatic hypotension, causing light‑headedness upon standing.

Serious

• Neuroleptic malignant syndrome, a rare but life‑threatening reaction characterized by fever, muscle rigidity, autonomic instability, and altered mental status.
• Tardive dyskinesia, characterized by involuntary movements of the face, tongue, or limbs after prolonged use, which may be irreversible.
• Significant cardiac arrhythmias, including QT interval prolongation that can predispose to torsades de pointes.

When prescribing haloperidol, clinicians consider several precautionary measures to minimize risk and ensure appropriate use.

• Assess patient history for cardiovascular disease, as haloperidol may affect heart rhythm.
• Evaluate for prior extrapyramidal reactions or movement disorders before initiating therapy.
• Use the lowest effective dose, especially in elderly patients, to reduce sedation and fall risk.
• Monitor for signs of neuroleptic malignant syndrome during the first weeks of treatment.
• Consider pregnancy and lactation status; haloperidol crosses the placenta and may be present in breast milk.
• Review liver and kidney function, adjusting dose if significant impairment is present.

Haloperidol can interact with other medicines, altering its effectiveness or increasing the risk of adverse effects.

Avoid

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

Use with caution

• CNS depressants like benzodiazepines or opioids, which may enhance sedation.
• Anticholinergic agents, as they can mask early signs of extrapyramidal symptoms.
• Lithium, because combined use may increase neurotoxicity.