Overdosage of Cetirizine hydrochloride (180 mg) caused restlessness, irritability and drowsiness in an 18-month old child. In adults, drowsiness, upon ingestion of 150 mg Cetirizine hydrochloride, has been reported.
A case of a hypokalemic dialyzed patient with chronic renal failure, was reported to develop symptomatic episodes of torsades de pointes after overdosage with Cetirizine hydrochloride.