Medications for Allergies

Allergies occur when the immune system overreacts to a normally harmless substance — called an allergen — treating it as a threat and triggering an inflammatory response. Common allergens include pollen, dust mites, pet dander, mold, certain foods (such as peanuts, shellfish, or milk), insect stings, and medications. Allergies are extremely common, affecting more than 50 million Americans, and can appear at any age, though they often first develop in childhood. Symptoms vary depending on the type of allergen and the body part exposed: respiratory allergies (hay fever) cause sneezing, runny or congested nose, and itchy eyes; skin allergies cause redness, itching, and rashes; and food or venom allergies can trigger a severe, whole-body reaction called anaphylaxis. The immune system releases histamine and other chemicals that drive these symptoms.

Severe allergic reactions (anaphylaxis) can cause a sudden drop in blood pressure, throat swelling, and difficulty breathing, requiring emergency treatment with epinephrine. Chronic allergies such as allergic rhinitis and eczema can significantly impact quality of life, disrupt sleep, and worsen asthma. Treatment depends on the type and severity of the allergy: antihistamines block the histamine response and are the most widely used allergy medications; nasal corticosteroid sprays reduce nasal passage inflammation for hay fever; decongestants relieve congestion; and leukotriene modifiers and allergen immunotherapy (allergy shots or sublingual drops) offer longer-term control. Epinephrine auto-injectors are prescribed to people at risk of anaphylaxis for emergency use. The medications listed below are among the most commonly prescribed for managing allergies.