Abstract Dystonic crises are usually associated with the antipsychotic phenothiazines. They are considered to be idiosyncratic reactions to phenothiazines as well as to other centrally acting agents such as the tricyclic antidepressants.1 The phenothiazine group of drugs represents a variety of agents that differ in their pharmacologic effects. Promethazine hydrochloride is usually employed for its H1 antihistaminic properties, and less frequently for its sedative-hypnotic effect. Some of its actions on the CNS have been ascribed to its potent anticholinergic activity.2,3 Textbooks of pharmacology and poisoning suggest that promethazine, like all other phenothiazines, can produce acute dystonic reactions.4 We found in the literature only one brief description of acute extrapyramidal manifestations caused by promethazine intoxication.5 Report of a Case.—A 2-year-old infant became lethargic after presumably ingesting promethazine syrup (Phenergan). An empty 240-mL bottle of the drug was found on the floor. She became unresponsive and difficult to References 1. Lader MH: Drug-induced extrapyramidal syndromes . J R Coll Physicians Lond 5:87-98, 1970. 2. Burt DR, Creese I, Snyder SH: Antischizophrenic drugs: Chronic treatment elevates dopamine receptor binding in brain . Science 197:326-328, 1977.Crossref 3. Shearer CM, Miller SM: Promethazine hydrochloride . Analytical Profiles of Drug Substances 5:65, 1975. 4. Drug Therapy: Neurologic syndromes associated with antipsychotic-drug use. American College of Neuropsychopharmacology, Food and Drug Administration Task Force . N Engl J Med 289:20-23, 1973.Crossref 5. Swaiman KF: Acute neurologic reactions to promethazine . N Engl J Med 263:747, 1960.Crossref 6. Fisher SE: Encephalitic reaction to promethazine J Pediatr 80:896-897, 1972.Crossref 7. Gupta JM, Lovejoy FH: Acute phenothiazine toxicity in childhood . Pediatrics 39:771, 1967. 8. Waterhouse RG: Epileptiform convulsions in children following premedication to pamergan SP 100 . Br J Anaesth 39:268-270, 1967.Crossref 9. Bunney BS, Walter JR, Roth RH, et al: Dopaminergic neurons: Effects of antipsychotic drugs and amphetamine on single cell activity . J Pharmacol Exp Ther 185:560-571, 1973. 10. Goth A: Antihistaminic drugs , in: Medical Pharmacology , ed 8. St Louis, CV Mosby Co, 1976, p 198.
American Journal of Diseases of Children – American Medical Association
Published: Oct 1, 1980