Has dose-related effects on ventricular repolarization leading to QTc prolongation. 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. Relative to other neuroleptics, thioridazine has high potency of cholinergic blockade. 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 (e.g. Alzheimer’s disease). May cause extrapyramidal symptoms, including pseudoparkinsonism, acute dystonic reactions, akathisia, and tardive dyskinesia (risk of these reactions low relative to other neuroleptics). 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. Mental status changes might occur (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. Highly sedating. Impaired core body temperature regulation may occur. Use with caution in severe cardiovascular disease. Elderly patients with dementia-related psychosis treated with antipsychotics are at increased risk of death compared to placebo. Increased incidence of cerebrovascular adverse events (including fatalities) reported in elderly patients with dementia-related psychosis. Use with caution in narrow-angle glaucoma (may be exacerbated by cholinergic blockade), in hepatic impairment. Use with caution in myasthenia gravis (may be exacerbated by cholinergic blockade). in Parkinson’s disease (may be more sensitive to adverse effects), 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.