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What Everyone Should Know About Peanut Allergies

Peanut allergies are one of the most common allergies in the world and they’re usually diagnosed in babies and children. Avoiding peanuts — and all the products that can contain them — can be overwhelming for parents.

“A peanut allergy is when someone’s immune system sees peanut protein as a threat and makes allergic antibodies to try and protect itself,” said Heather Cassell, MD, a pediatric allergy and immunology specialist with Banner – University Medicine.

If you have a peanut allergy, ingesting even a small number of peanuts can trigger an allergic reaction. “The symptoms can vary from person to person. A reaction can be as mild as an itchy mouth and a few hives, all the way to breathing troubles and loss of blood pressure,” Dr. Cassell said.

Because peanut allergies can be so serious, activities that are mainly harmless for most children, like block parties, baseball games and sleepovers with friends, can be dangerous situations for those with peanut allergies. 

Knowing how to manage them is key. “Families have a challenging task with balancing safety and fear of anaphylaxis with having a normal life,” Dr. Cassell said.

Peanut allergies can cause a lot of stress and anxiety for the families dealing with them.  “Patience and understanding are important in supporting your friends and family members who deal with food allergies,” Dr. Cassell said. 

Symptoms to watch for with a peanut allergy

Someone with this allergy who comes into contact with peanuts may have symptoms such as:

  • Itching: Often starts around the mouth or on the skin where peanuts are contacted.
  • Hives: Raised red welts on the skin that might itch.
  • Swelling: Usually in the face and throat and sometimes in other body parts.
  • Runny or stuffy nose: Often with sneezing.
  • Digestive issues: Nausea, vomiting, diarrhea or abdominal pain.
  • Difficulty breathing: Shortness of breath, wheezing or tightness in the throat.
  • Anaphylaxis: The person’s airways narrow, blood pressure drops, pulse is rapid and weak and the body goes into shock and may lose consciousness. Anaphylaxis can happen in severe cases and is life-threatening.

How are peanut allergies diagnosed?

If you think you or your child might have a peanut allergy, talk to your health care provider. “A careful history can often suggest a peanut allergy, but blood and/or skin testing can confirm this. These tests can also sometimes have a false positive, meaning the test suggests an allergy but the person does not really have one,” Dr. Cassell said.

Here’s how testing works:  

  • Skin prick test: A health care provider puts a small amount of peanut extract on the skin, usually on the forearm or the back. Then they prick the skin with a needle, so a tiny amount of the allergen goes underneath the skin. If a raised bump (wheal) surrounded by redness (flare) shows up within 15 to 20 minutes, it's a sign of a possible allergic reaction.
  • Blood test: A health care provider takes a blood sample and has it analyzed in a laboratory to check the immune response to peanuts. It measures the peanut-specific antibodies (IgE) in the blood. Results are usually ready in a few days.
  • Food challenge: With this test, you eat the food under medical supervision to make sure there aren’t any reactions. “That’s the gold standard,” Dr. Cassell said. It’s important to only try a food challenge with a health care provider’s guidance. Don’t try it on your own.

Along with testing, it's also important to keep a food diary to look for possible triggers and patterns related to peanut allergies.

You'll want to:

  • Track all foods eaten, including meals and snacks.
  • Record any symptoms that start soon after having peanuts or products that contain peanuts, like itching, hives or an upset stomach.
  • Note whether symptoms improve when you don't have any peanuts or products that contain peanuts.
  • Share your food diary with health care providers so they can use it to look for patterns, recommend tests and suggest strategies for living with allergies.

Managing peanut allergies

When you're living with peanut allergies, you'll want to avoid peanuts, prepare for emergencies and consider treatment options.

Here are some steps you can take:

  • Read food labels: Check for peanuts, peanut products and cross-contamination warnings. Dr. Cassell pointed out that cautionary labels that use phrases like “may contain” or “shared equipment” are voluntary. “I don’t tell people to avoid those foods, especially if they’re made by large companies since they probably aren’t using shared equipment. Every family needs to do what they feel comfortable with, but the risk is extraordinarily low.”
  • Inform others: Tell family members, friends, teachers, administrators, colleagues and restaurant staff about peanut allergies to make it less likely that you are exposed accidentally. Let the people closest to you know how to recognize symptoms and what to do in an emergency.
  • Avoid cross-contact: Be careful of shared cooking utensils and food prep surfaces during food preparation.
  • Carry an epinephrine auto-injector or inhaler: You should have an epinephrine auto-injector (EpiPen) or inhaler with you all the time and know how to use it in case of a severe allergic reaction (anaphylaxis). An inhaler was recently approved, although the dose is too large for young children. It may be an option for older children and adults.
  • Try antihistamines: These can help relieve mild allergy symptoms, but they don’t replace epinephrine during severe reactions.
  • Evaluate restaurants: Choose places that are knowledgeable about food allergies and ask about ingredients and food preparation. Let your server know about your allergy even if you’re ordering something that wouldn’t contain peanuts. Be careful of cross-contamination in buffet or self-serve restaurants.
  • Be careful in social settings: Ask your host about the menu ahead of time and offer to bring a safe dish to share.
  • Travel safely: Pack safe snacks, notify your airline and request a peanut-free meal. Learn how to communicate your allergy in the language of the country you are visiting. Research common local dishes that may contain peanuts.

“Avoidance and carrying an epinephrine autoinjector are the most important. While there is no cure, there are other possible treatments available which can be discussed with a board-certified allergist,” Dr. Cassell said.

Treating peanut allergies

You might be able to treat a peanut allergy with immunotherapy. That involves gradually exposing the body to small, controlled amounts of peanuts to desensitize the immune system over time. It’s approved for people over age 1.

“This is only to be done by an experienced allergist because of the risk for anaphylaxis,” Dr. Cassell said.

Immunotherapy might reduce the severity of allergic reactions from being accidentally exposed to peanuts. However, not everyone is a candidate and results may vary. 

Watch out for these foods

It's pretty clear that you need to avoid peanuts and peanut butter if you have a peanut allergy. But peanuts can hide in other foods, too:

  • Processed foods like baked goods, candies and sauces may have small amounts of peanuts.
  • Natural and artificial flavors sometimes contain peanut products.

Even if food has been safe to eat every time, depending on where it is made, the recipes could change. In addition, many people who have peanut allergies are also allergic to tree nuts like almonds, cashews and walnuts. You'll want to read food labels carefully and talk to your health care provider about strategies to avoid foods that might contain peanuts.

When to get emergency care

You’ll want to use an epinephrine auto-injector (EpiPen) and call 911 for:

  • Difficulty breathing, wheezing or tightness in the throat. 
  • Swelling in the lips, face, tongue or throat that makes it hard to swallow or breathe. 
  • Hives that come on quickly.
  • Widespread itching.
  • Confusion, dizziness, fainting or loss of consciousness, which could be signs of a major drop in blood pressure.
  • Rapid or weak pulse.
  • Vomiting, diarrhea or severe abdominal pain.

Be prepared to give a second dose of epinephrine if symptoms don’t improve, or they get worse before emergency responders arrive. 

The bottom line

Peanut allergies can trigger serious immune reactions, from mild symptoms like itching and hives to life-threatening anaphylaxis. To manage a peanut allergy, you need to avoid peanuts and products that contain peanuts, read food labels and be prepared with epinephrine (EpiPen) in case of accidental exposure. 

Talk to your health care provider or an expert at Banner Health for advice on diagnosing, managing and treating peanut allergies so you can stay safe and improve your quality of life.

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