what category of drugs is antihistamines
Allergy medication list. Antihistamines used to treat allergy symptoms fall into two broad categories: sedating and non-sedating. The first category includes the older antihistamines. These allergy drugs relieve allergy symptoms but cause drowsiness and other side effects, including dry mouth. Newer antihistamines are said to be non-sedating, although some users may experience drowsiness even from these.