Trends and toxic effects from pediatric clonidine exposures

Objective: To analyze the trends, demographics, and toxic effects associated with pediatric clonidine hydrochloride exposures reported to poison centers. Design: Retrospective. Setting and Patients: Clonidine-only exposures followed up to known outcome in children younger than 19 years reported to the American Association of Poison Control Center's database from January 1, 1993, through December 31, 1999. Main Outcome Measures: Frequency of exposures over time, acuity, reason, symptoms, management site, treatment, and outcome. Results: There were 10 060 reported exposures with 57% reported for children younger than 6 years, 34% for children between 6 and I years old, and 9% for adolescents between 13 and 18 years old. In 1999 there were 2.5 times as many exposures as in 1993. In 6- through 12-year-olds, clonidine was the child's medication in 35% of the exposures, compared with 10% in children younger than 6 years and 26% in adolescents. The proportion of cases involving the child's medication increased over 7 years. While unintentional overdose was most common in children younger than 6 years, therapeutic errors and suicide attempts predominated in 6- through 12-year-olds and adolescents, respectively. In 6042 symptomatic children (60%), the most common symptoms were lethargy (80%), bradycardia (17%), hypotension (15%), and respiratory depression (5%). Most exposures resulted in no effect (40%) or minor effects (39%). Moderate effects occurred in 1907 children (19%), major effects in 230 children (2%); there was I fatality in a 23-month-old. Conclusions: While most of the clonidine exposures resulted in minimal toxic effects, serious toxic effects and death can occur. The trend toward increasing the number of exposures in children, especially with evidence of toxic effects in children receiving clonidine therapeutically, is cause for concern.