Background: With the rising number of prescriptions for methylphenidate has come an increase in preschool younger siblings being exposed to the risk of ingesting methylphenidate. Furthermore, the symptoms of methylphenidate ingestion in preschool children have not been previously defined.
Methods: Over a 3-year period we enrolled and followed by telephone children aged <6 years with methylphenidate ingestion, whether it was their own medication or someone else's, at time of first call to the poison control center.
Results: A total of 49 children aged 30+/-11 months were included. Patients ingested a median of 1 tablet (range 0.25-10) for a total median dose of 0.9 mg/kg (range 0.26-12). Twenty-one patients were referred to a health care facility, and the poison control center recommended activated charcoal for 12 of them. Patients referred to a health care facility ingested more methylphenidate: median 1.8 versus 0.7 mg/kg (P<0.001). Patients for whom activated charcoal was recommended ingested more methylphenidate: median 3.5 versus 0.8 mg/kg (P<0.001). Twenty-four patients developed symptoms: agitation or irritability in 17, somnolence in 5, vomiting in 2, and abdominal pain in 2. Two patients had tachycardia. Patients who ingested an extended-release preparation had similar rates of symptoms as those who ingested a regular preparation, 7/9 versus 17/40 (P=0.07), while having ingested similar amounts, median 1.6 versus 0.8 mg/kg (P=0.08). Patients who ingested 1 tablet or less had a similar rate of symptoms as those who ingested more than 1 tablet: 12/29 versus 10/17 (P=0.25). There was no difference in the dose ingested for those who became symptomatic compared with those who remained asymptomatic: median 1.2 (range 0.26-12) versus 0.8 mg/kg (range 0.26-3.8) (P=0.08).
Conclusion: Preschool children ingesting less than 1 mg/kg of regular methylphenidate can be safely managed at home in spite of the fact that some will develop minor symptoms.