Cetirizine Consumption: When an Antihistamine Sparks an Unexpected Medical Twist in a Toddler – A Case Report of Somnolence and Bradycardia

We report the case of a 2-year-old boy who ingested approximately half a bottle of cetirizine syrup (~15 mg total).Within one hour, the child developed notable somnolence and bradycardia (heart rate ~60-76 bpm), though respiratory function and capillary refill time remained stable.He was managed with supportive care and admitted for close observation.Over a six-hour period, the somnolence and bradycardia gradually resolved without intervention.The child was discharged after 13 hours of monitoring in stable condition, having returned to baseline neurological and cardiovascular function.Although cetirizine has a wide therapeutic index, this case highlights that overdose in young children can cause transient cardiovascular and CNS effects.Timely recognition, conservative management, and observation are usually sufficient for complete recovery.Cetirizine poisoning in children is generally self-limiting, but may present with somnolence and bradycardia.Prompt observation and supportive care lead to favorable outcomes.