Background: Diphenhydramine is frequently used in children, but the consequences of single unintended dose exposures in young children are unknown.
Methods: We evaluated 2000-2001 American Association of Poison Control Centers-Toxic Exposure Surveillance data on children exposed to diphenhydramine ingestions.
Results: Nine hundred twenty-six cases met the inclusion criteria; 49.1% were men, mean age was 29.7 ± 13.0 months (range, 1-72 months). Approximately 85% of unintentional exposures occurred in 1- to 3-year-old children. The mean dose ingested was 6.4 ± 6.1 mg/kg (median, 4.6 mg/kg). Thirty-two percent of patients were symptomatic: minor (29.4%), moderate (2.9%), and severe (0.11%). There was no relationship between dose and symptom severity. Diphenhydramine dose ingestion of 7.5 mg/kg or greater was not a predictor of severity (P = 0.47)
Conclusions: The relationship between ingested dose and severity of symptoms was insignificant.