A peanut allergy occurs when the body responds abnormally to peanuts. The reaction may range from mild to life-threatening. Even a small amount of peanuts can lead to a serious reaction.

This condition may be serious. It requires care from a doctor.


The allergy occurs when your body is exposed to peanut proteins. The body mistakes the proteins as harmful substances, and the immune system releases chemicals into the bloodstream, which causes symptoms .

Coming in contact with peanuts can occur by:

  • Eating peanuts, foods containing them, or foods that came in contact with them
  • Touching peanuts
  • Inhaling particles containing peanuts, such as peanut flour
  • Risk Factors

    Peanut allergy, like other food allergies , is more common in children. Other factors that may increase your chance of a peanut allergy include:

  • Other allergies, such as food or hay fever
  • Personal or family history of allergies
  • Chronic inflammation of the outer layers of the skin— atopic dermatitis
  • Symptoms

    Peanut allergy may cause:

  • Redness or swelling of the skin— hives
  • Itching or tingling of the mouth and throat
  • Diarrhea
  • Stomach cramps
  • Nausea
  • Vomiting
  • Shortness of breath or wheezing
  • Chest tightness
  • Runny or stuffy nose
  • Hives

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    Anaphylaxis is a serious, life-threatening allergic reaction. Anaphylaxis may cause:

  • Closing of airways or swelling of throat, making it very hard to breathe
  • Severe drop in blood pressure
  • Very fast pulse
  • Lightheadedness
  • Loss of consciousness
  • If you have a serious allergic reaction or are with someone who does, call for emergency medical services or go to the nearest emergency room right away.


    You may be referred to a doctor who specializes in allergies. The doctor will:

  • Ask about your symptoms
  • Take your medical history
  • Do a physical exam
  • Tests may include:

  • Skin prick test—To look for a skin reaction when exposed to specific food particles
  • Blood test—To look for an antibody called immunoglobulin E (IgE), which is present when you are exposed something that gives you an allergic reaction
  • Food Diary

    You may be asked to keep a food diary. This means you will write down your experiences with food, such as your eating habits and symptoms. This may help the doctor find out what food(s) may be causing your allergies.

    Elimination Diet

    You may be placed on an elimination diet to learn which foods may be triggering an allergic reaction. If your doctor thinks you might be allergic to peanuts, you may be asked to remove peanuts from your diet for 1-2 weeks then add them back to your diet to see if you experience any symptoms. The elimination diet is only done under a doctor’s supervision.


    Talk with your doctor about the best treatment plan for you. Options include:

    Avoid Peanuts

    The best treatment is to avoid peanuts, foods containing them, and foods that may have been exposed to them. Always read ingredient labels, even if you do not think the food contains peanuts. Most food labels will state whether the factory where a food was made also processes peanuts. If offered homemade foods, always ask about the ingredients to check for the presence of peanuts or peanut oil.


    If you do have a mild allergic reaction, you may be able to take antihistamines to reduce symptoms, like itching or hives. Talk with your doctor about medications that are right for you.

    Epinephrine Injection

    For severe allergic reactions, you may need to inject yourself with epinephrine. Epinephrine is injected using an auto-injector (EpiPen, Twinject), which contains a syringe, needle, and a dose of the the medication. You inject the medication into your thigh. You should carry an auto-injector with you at all times.

    For any severe reaction, call for emergency medical services or go to the nearest emergency room right away.


    If you are pregnant and do not have a peanut allergy, you may want to consider consuming peanuts to lower the risk that your child will have a peanut allergy.

    To help reduce your chance of a reaction to peanuts:

  • Avoid peanuts, peanut-containing products, and foods that were exposed to peanuts. For instance, when placing an order at a restaurant, ask the server if the dish contains peanuts or is cooked with items (sauces or oils) that may contain peanuts.
  • Read food labels and other labels, such as medications, make-up, or face cream labels. You never know what items may contain peanuts.
  • Here are some foods that may contain peanuts or may have been made in factories that process peanuts:

  • Cookies
  • Pastries
  • Ice cream
  • Energy bars
  • Cereal
  • Bread
  • Salad dressing
  • Chocolate candies
  • Nut butters and oils
  • Sauces and gravies
  • Vegetarian food products, such as veggie burgers
  • The list may be endless. This is why it is very important to be aware of what you are eating or come in contact with. Even the smallest amount of peanut protein can trigger a life-threatening response.