Taking too much antihistamine can lead to adverse side effects and a potential antihistamine overdose. Signs may include fast heart rate, fever, and dilated pupils. People should follow the dosage ...

Types of nasal antihistamine sprays include azelastine (brand names include Astepro and Astelin) and olopatadine (brand names include Pazeo and Pataday). Nasal corticosteroid sprays help make ...