Allergies occur when your immune system reacts to a foreign substance — such as pollen, bee venom or pet dander — that doesn’t cause a reaction in most people.

The severity of allergies varies from person to person and can range from minor irritation to anaphylaxis — a potentially life-threatening emergency. While most allergies can’t be cured, a number of treatments can help relieve your allergy symptoms.

Allergy Types

Food Allergies. People often have an unpleasant reaction to something they ate and wonder if they have a food allergy.

  • Milk Allergy
  • Egg Allergy
  • Wheat Allergy
  • Nut (Peanut) Allergy
  • Fish Allergy
  • Sulfite Allergy
  • Soy Allergy
  • Casein Allergy

Seasonal Allergies

  • Spring Allergies
  • Summer Allergies
  • Fall Allergies
  • Winter Allergies

Pet Allergies

  • Dog Allergy
  • Cat Allergy

Other Allergies

  • Hay Fever
  • Allergic Conjunctivitis (Pink Eye)
  • Hives (Urticaria)
  • Allergies to Poison Ivy, Oak, and Sumac
  • Allergies to Insect Stings (Bee Stings)
  • Mold Allergy
  • Pollen Allergies
  • Sun Reactions of the Skin
  • Aspirin Allergy (Salicylate Allergy)
  • Cosmetic Allergy
  • Nickel Allergy
  • Drug Allergy
  • Dust Allergy
  • Chemical Allergy
  • Penicillin Allergy


Allergy Symptoms

Mild Allergy Symptoms

Mild allergy symptoms can include:

  • Rash
  • Localized itching
  • Congestion

Moderate Allergy Symptoms

  • Widespread itching
  • Difficulty breathing

Severe Allergy Symptoms (Anaphylaxis)

  • Anaphylaxis is a rare, life-threatening emergency in which the body’s response to the allergen is sudden and affects the whole body. Allergy symptoms may within minutes progress to more serious symptoms, including:
    • Itching of eyes or face
    • Varying degrees of swellings that can make breathing and swallowing difficult
    • Abdominal pain
    • Cramps
    • Vomiting
    • Diarrhea
    • Mental confusion or dizziness


To evaluate whether you have an allergy, your doctor may:

  • Ask detailed questions about signs and symptoms
  • Perform a physical exam
  • Have you keep a detailed diary of symptoms and possible triggers

If you have a food allergy, your doctor may:

  • Ask you to keep a detailed diary of the foods you eat
  • Have you eliminate a food from your diet (elimination diet) — and then have you eat the food in question again to see if it causes a reaction

Your doctor may also recommend one or both of the following tests:

  • Skin test. Your skin is pricked and exposed to small amounts of the proteins found in potential allergens. If you’re allergic, you’ll likely develop a raised bump (hive) at the test location on your skin. Allergy specialists usually are best equipped to perform and interpret allergy skin tests.
  • Blood test. A blood test that’s sometimes called the radioallergosorbent test (RAST) can measure your immune system’s response to a specific allergen by measuring the amount of allergy-causing antibodies in your bloodstream, known as immunoglobulin E (IgE) antibodies. A blood sample is sent to a medical laboratory, where it can be tested for evidence of sensitivity to possible allergens.



Allergy treatments include:

  • Allergen avoidance. Your doctor will help you take steps to identify and avoid your allergy triggers. This is generally the most important step in preventing allergic reactions and reducing symptoms.
  • Medications to reduce symptoms. Depending on your allergy, allergy medications can help reduce your immune system reaction and ease symptoms. Medications can include over-the-counter or prescription medications in the form of oral medications, nasal sprays or eyedrops.
  • Immunotherapy. For severe allergies or allergies not completely relieved by other treatment, your doctor may recommend allergen immunotherapy. This treatment involves a series of injections of purified allergen extracts, usually given over a period of a few years.
Another form of immunotherapy is a tablet that’s placed under the tongue (sublingual) until it dissolves. Sublingual drugs are used to treat some pollen allergies.
  • Emergency epinephrine. If you have a severe allergy, your doctor may give you an emergency epinephrine shot to carry with you at all times. Given for severe allergic reactions, an epinephrine shot (EpiPen, Auvi-Q, others) can reduce symptoms until you get emergency treatment.

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