Characterization of methylphenidate exposures reported to a regional poison control center.

OBJECTIVE: To investigate the frequency, risk population, symptoms, reason, and outcome surrounding human methylphenidate exposures reported to a regional poison control center.
DESIGN: Retrospective case series. SETTING/PATIENTS: All human methylphenidate exposures reported to a regional poison control center during a 2-year period were included. MAIN OUTCOME MEASURES: Data collected included age, dose, reason for exposure, symptoms (type and severity), treatment, and outcome. Age data for all other exposures reported during the same time period were also compiled.
RESULTS: The study included 289 patients. Overall, 31% developed symptoms, most commonly tachycardia, agitation, and lethargy. No patient developed severe symptoms, although a less favorable outcome was seen with intentional vs unintentional exposures. When compared with the age data for all other exposures reported during the same time period, a trimodal vs bimodal pattern was seen, with the novel peak occurring in 6- to 9-year-old children. Within this age group, therapeutic error was the most common reason for exposure.
CONCLUSIONS: Methylphenidate exposure was associated with symptom development in 31% of cases. An unusually high incidence of therapeutic error was noted surrounding its use, most commonly in the 6- to 11-year-old age group, defining a unique population at risk for toxic exposure. This initial data may allow targeted poisoning prevention efforts for this age group. Arch Pediatr Adolesc Med. 2000;154:1199-1203.