The Ingredients of Antihistamines

Antihistamines are an effective group of drugs to treat allergic reactions. These drugs fight allergies by preventing more production of histamines in the body, and not necessarily reversing the effects of the illness. When an antihistamine is taken, it prevents the histamine from reaching the receptors on cells at the site where the reaction or irritation is taking place. Some antihistamines are designed to block receptors all throughout the body causing extreme drowsiness. Some doctors would even recommend antihistamines to actively treat insomnia. Newer antihistamines are now designed to target only specific areas of the body to give a localized effect without making the patient drowsy. In addition, more powerful antihistamines are now available for adverse allergic reactions.

Recent versions of antihistamines also now contain anticholinergics, medications that dramatically limit the secretion of acetylcholine from the receptor sites in the brain and throughout the body. Acetylcholine is a vital neurotransmitter that is involved in the communication between motor nerves and muscles. Blocking this receptor can effectively treat allergy symptoms. The ingredients in antihistamines that make this happen are chlorcyclizine hydrochloride, Brompheniramine maleate, chlorpheniramine maleate, and dexbrompheniramine maleate. These ingredients are common in most over-the-counter antihistamine drugs and prescription antihistamines as well.