Common Medications Prescribed

Antihistamines block histamine, the substance released when cells recognize allergens. Antihistamines relieve redness, inflammation, itchiness and watery eyes. Many older antihistamines can make you feel drowsy. Newer, non-sedating ones are available, most by prescription. Dry mouth is common.

Decongestants reduce nasal congestion by constricting blood vessels, effectively decreasing the amount of fluid that leaks out into the mucus. Nasal sprays work quicker than oral decongestants, but a rebound effect is common. After a few days of taking nasal decongestants, the congestion that the medication had cleared comes back. More medication makes the congestion worse. Decongestants are available over-the-counter and through prescription.

Leukotriene antagonists are medications that can block leukotrienes, which are chemicals produced by cells that cause airway inflammation. This chemical worsens inflammation and causes the airway muscle to contract. It also increases fluid leaking from blood vessels in the lungs. Leukotriene antagonists effectively reduce mucous production.

Bronchodilators relax the muscles around the air tubes in the lungs. They are used to decrease allergy symptoms such as coughing, wheezing and shortness of breath. Agitation and nervousness are common side effects.

Steroids taken by mouth or inhaled through the nose decrease inflammation. Nasal steroids have fewer side effects than oral forms. Oral use for more than a week should be monitored by a doctor. Low dose steroids placed on the skin help with rashes.

Immunotherapy

If the symptoms cannot be controlled by avoiding triggers and using medication, your doctor may try immunotherapy, or allergy desensitization shots. Allergy shots are like vaccinations. Through exposure to small, injected amounts of a particular allergen in gradually increasing doses, your body builds up immunity. The next time your body encounters these allergens, you have less of a chance of having an allergic response or you have a very minor response and fewer symptoms.

Immunotherapy works best for allergies to pollen, mold, cat dander, insect stings and dust mites. You might have some swelling at the site of the injection. Rarely, there might be a serious allergic reaction leading to asthma symptoms or anaphylaxis.

Very fine needles are used for the injections, and the needle only goes just below the skin's surface. While the needle doesn't usually hurt, the injected solution can be irritating and cause itching or a stronger reaction.

More on Allergies

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This article was reviewed and updated June 2007.