Chloropyramine Products | Cleanchem - Chloropyramine is an antihistamine used to treat allergic conditions such as hay fever, rhinitis, and urticaria (hives). It works by blocking histamine receptors, reducing allergic symptoms like itching, swelling, and redness. Chloropyramine is also used as a sedative for its calming effects, especially in treating anxiety. Common side effects include drowsiness, dry mouth, and dizziness.