An allergy is an abnormal reaction to certain substances called allergens. These allergens may be inhaled, swallowed, or come in contact with the skin to trigger a reaction.

Overview and Symptoms

Common allergens include:

  • Environmental allergens such as pollen, animal dander, and dust that can cause allergic reactions like watery or itchy eyes, sneezing, and coughing
  • Insect stings from yellow jackets, honeybees, paper wasps, and hornets which, if the person is allergic to the insect’s venom, can result in a medical emergency called anaphylaxis
  • Indoor and outdoor mold spores
  • Foods that the body mistakes for something harmful; an allergic reaction to food can affect the skin, stomach and intestines, and breathing
  • Products that contain latex, which may lead to mild or serious allergic reactions
  • Medications may cause allergic reactions that range from mild to serious


Allergy treatment is guided by the type and severity of the allergy. They may include:

  • Avoiding contact with substances that trigger the allergy
  • Over-the-counter medications such as antihistamines and decongestants
  • Prescription medications in the form of nasal sprays, tablets, or eye drops
  • Allergy shots
  • Other medications to counteract allergic reactions or treat specific symptoms

Learn More

The Division of Allergy and Inflammation specializes in the diagnosis, testing, and management of allergies, asthma and allergic immune system disorders.

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