Zyrtec-D Overdosage

Information on overdosing with respect to fixed combinations of cetirizine and pseudoephedrine is not available.
The information hereinafter is based on information from experience with cetirizine and pseudoephedrine used as mono preparations.
Symptoms: Cetirizine-component: The symptoms that were observed in cases of clear overdose affected the central nervous system or were related to a possible anticholinergic effect. Adverse effects that were observed after taking at least the five-fold quantity of the recommended daily dosage included the following: confusion, diarrhea, numbness, tiredness, headache, unwellness, mydriasis, pruritis, restlessness, sedation, somnolence, stupor, tachycardia, tremor, urinary retention.
Pseudoephedrine-component: Possible symptoms and signs after an overdose of pseudoephedrine are hypertension, tachycardia, sinus arrhythmia, drowsiness, nausea, vomiting, mydriasis, agitation, tremor, hyperreflexia, hallucinations and generalized seizures.
Action to be taken in the case of overdose (measures for a combination of the two substances): Treatment of an overdose is purely symptomatic. There is no known specific antidote. Activated charcoal at a dose of 1 g/kg body weight may be given for primary decontamination after the ingestion of large quantities.
Tachycardia and hypertension may occur but often do not require any treatment. Administration of a benzodiazepine is recommended for agitated patients with hypertension/tachycardia. If progression of these effects is severe, the use of labetalol, phentolamine or nitroprusside may be considered. Benzodiazepines are also the drugs of first choice for agitation and seizures.
Haemodialysis is not effective for either substance.