May alter cardiac conduction (life-threatening arrhythmias occurred with therapeutic doses of phenothiazines). May cause anticholinergic effects (constipation, xerostomia, blurred vision, urinary retention)(use with caution in decreased gastrointestinal motility, paralytic ileus, urinary retention, BPH, xerostomia, or visual problems). Blood dyscrasias might occur (use contraindicated in bone marrow suppression). 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 EPS) may be greater with increased doses, use of conventional antipsychotics, males, and younger patients. 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 risk of cerebrovascular disease, cardiovascular disease, hypovolemia, or concurrent medication use which may predispose to hypotension/bradycardia). May cause photosensitization. May be associated with pigmentary retinopathy. May cause sedation. Impaired core body temperature regulation may occur. Use with caution in severe cardiovascular disease. Perphenazine not approved for dementia-related psychosis. Use with caution in depression (possibility of increased risk of suicide), in narrow-angle glaucoma (may be exacerbated by cholinergic blockade), in myasthenia gravis (may be exacerbated by cholinergic blockade), and in Parkinson’s disease. Use with caution in breast cancer or other prolactin-dependent tumors (elevates prolactin levels), in hepatic or 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), and in reduced functional alleles of CYP2D6 (poor metabolizers).