Why it's dangerous
Antihistamines affect the central nervous system and cardiovascular system, leading to a range of symptoms from sedation to severe agitation and respiratory depression.
Toxic compound: diphenhydramine
Good to know
Commonly used in both human and veterinary medicine for allergies and skin disease; accidental ingestion can be fatal.
Sources
This page is informational and is not veterinary advice. If your pet has been exposed to something risky, contact your vet or an animal poison control line right away.