May alter cardiac conduction (life-threatening arrhythmias occurred with therapeutic doses of phenothiazines). May cause anticholinergic effects (use with caution in decreased GI motility, paralytic ileus, urinary retention, benign prostatic hypertrophy, xerostomia, or visual problems). Antipsychotic use associated with esophageal dysmotility and aspiration (use with caution in risk of pneumonia). May cause extrapyramidal symptoms, including pseudoparkinsonism, acute dystonic reactions, akathisia, and tardive dyskinesia. Risk of dystonia (and possibly other extrapyramidal symptoms) may be greater with increased doses, use of conventional antipsychotics, males, and younger patients. Hypotension may occur following administration, particularly when parenteral form used, or high dosages. May be associated with neuroleptic malignant syndrome (risk may be increased in Parkinson’s disease or Lewy body dementia). May cause orthostatic hypotension (use with caution in cerebrovascular disease, cardiovascular disease, hypovolemia, or concurrent medication use which may predispose to hypotension/bradycardia). May be associated with pigmentary retinopathy. May cause sedation. Impaired core body temperature regulation may occur. Use with caution in bone marrow suppression (blood dyscrasias occurred), and in severe cardiovascular disease. Prochlorperazine not approved for dementia-related psychosis (increased incidence of cerebrovascular adverse events, including fatalities). Use with caution in narrow-angle glaucoma (may be exacerbated by cholinergic blockade), in hepatic impairment, in myasthenia gravis (may be exacerbated by cholinergic blockade), and in Parkinson’s disease (may be more sensitive to adverse effects). Use with caution in breast cancer or other prolactin-dependent tumors (elevates prolactin levels), in renal impairment, in respiratory disease, and in risk of seizures, including patients with history of seizures, head trauma, brain damage, alcoholism, or concurrent therapy with medications which may lower seizure threshold. May mask toxicity of other drugs or conditions (e.g. intestinal obstruction, Reye’s syndrome, brain tumor) due to antiemetic effects. Effects may be potentiated when used with other sedative drugs or ethanol. Use with caution in the elderly (increased risk for developing tardive dyskinesia). Children with acute illness or dehydration are more susceptible to neuromuscular reactions (e.g. dystonias).