Clonidine poisoning in young children.

We reviewed 47 consecutive inpatient records to determine the clinical course, role of supportive measures, and response to naloxone in children with clonidine poisoning. Severity of illness was assigned by means of the "pediatric risk of mortality" (PRISM) score. The children's ages ranged from 9 to 84 months. Central nervous system effects were noted in 44 patients; bradycardia occurred in 25, and apnea or depressed respiration was seen in 18. Thirty-four patients had symptoms within 1 hour of presentation, but no patient had further clinical deterioration more than 4 hours after presentation. Six patients required endotracheal intubation and mechanical ventilation. There was no difference in PRISM score or duration of symptoms between those patients who received naloxone and those who did not. More patients receiving naloxone required intubation, and only three patients had definite improvement after naloxone administration. We conclude that (1) young children who ingest clonidine have a wide spectrum of serious findings, (2) delayed progression of symptoms after clonidine poisoning is unlikely in a young child with normal renal function, and (3) naloxone is an inconsistent antidote for clonidine poisoning.