The patient should be induced to vomit, even if emesis has occurred spontaneously. Pharmacologically induced vomiting by the administration of ipecac syrup is a preferred method. However, vomiting should not be induced in patients with impaired consciousness. Following emesis, any drug remaining in the stomach may be absorbed by activated charcoal administered as a slurry with water. If vomiting is unsuccessful or contraindicated, gastric lavage should be performed.
Dialysis is of little value in antihistamine poisoning.
After emergency treatment the patient should continue to be medically monitored. Treatment of the signs of symptoms of overdosage is symptomatic and supportive. Vasopressors may be used to treat hypotension. Short-acting barbiturates, diazepam, or paraldehyde may be administered to control seizures. Hyperpyrexia, especially in children, may require treatment with tepid water sponge baths or a hypothermic blanket.