Toxic clonidine ingestion in children.

Abstract

We performed a prospective case series to seek dosage or clinical parameters to better identify patients who need direct medical evaluation. All clonidine ingestions in children younger than 12 years of age reported to 6 poison centers were followed for a minimum of 24 hours. Exclusion criterion was polydrug ingestion. The study included 113 patients, of whom 63 were male. Mean age was 3.8 years (+/-2.4 SD). Clinical effects were common, but severe adverse effects occurred in <10% of patients. The dose ingested was reported for 90 patients (80%); 61 (68%) children ingested <0.3 mg and none had coma, respiratory depression, or hypotension. The lowest dose ingested by history with coma and respiratory depression was 0.3 mg (0.015 mg/kg). Prior clonidine therapy did not affect outcome. Onset of full clinical effects in all cases was complete within 4 hours of ingestion. We recommend direct medical evaluation for (1) all children 4 years of age and younger with unintentional clonidine ingestion of >or=0.1 mg, (2) ingestion of >0.2 mg in children 5 to 8 years of age, and (3) ingestion of >or=0.4 mg in children older than 8 years of age. Observation for 4 hours may be sufficient to detect patients who will develop severe effects.