Medically reviewed by Corinne Savides Happel, MD If you're pregnant, you may wonder if it's safe to use antihistamines. An estimated 10% to 15% of pregnant people do use these drugs to treat allergic ...

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 ...