Substance
Phenothiazines and neuroleptics

Pathology
Prominent cardiovascular and CNS effects; toxicity due to inhibitory effects of dopaminergic, cholinergic, alpha-adrenergic, histaminic, and serotonergic receptors.

Symptoms
Sedation, somnolence, stupor, dry mouth, tachycardia, labile blood pressure, hypothermia or hyperthermia, dysrhythmias, extrapyramidal symptoms, coma, NMS, seizures, cardiac arrest, death, akathisias.

Emergency Measures
Maintain airway and provide ventilatory and circulatory support if necessary. Decontaminate the GI tract. Follow standard ACLS protocols for managing cardiac rhythm disturbances. Give diphenhydramine or benztropine for dystonias. Bromocriptine, benzodiazepines, and/or dantrolene may be helpful in NMS.

Comments
Although death from neuroleptic overdose is rare, NMS may be fatal in 20% or more of affected patients.