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Tree Nut Allergy

There are many kinds of tree nuts: almonds, cashews, and walnuts are well-known examples.

Tree nut allergies are a common type of food allergy for both children and adults.1 A tree nut allergy, like any allergy, is when your immune system identifies something you eat or come in contact with, as harmful. When you eat or even touch tree nuts, the proteins cause your immune system to respond and release histamines, which then cause your allergic symptoms. An allergy to tree nuts could result in anaphylaxis—a life-threatening allergic reaction. 2,3

Unfortunately, a tree nut allergy usually lasts a lifetime—fewer than 10% of people outgrow it.4 Some people who have previously had severe reactions to tree nuts will eventually outgrow their tree nut allergy. So, the severity of your reaction doesn’t necessarily mean you won’t outgrow the allergy.    


Seed & Nut Allergy

Tree nut allergy symptoms

Other symptoms of a tree nut allergy may include:

  • Intense itching
  • Digestive symptoms (e.g. stomach pain, diarrhea, nausea)
  • Difficulty swallowing
  • Shortness of breath
  • Nasal congestion or a runny nose
  • Vomiting
  • Itching of the mouth, throat, eyes, skin or any other area
Anaphylaxis warning icon

Tree nut allergies are among the most common causes of anaphylaxis.2,3 People with a severe tree nut allergy should be prepared to respond to an anaphylactic reaction at all times. 

Learn more about anaphylaxis >

Tree Nut Allergy Testing

Ask Questions. Get Answers.

“Am I allergic to tree nuts?” isn’t a simple “yes” or “no” question, and not just because there are many kinds of tree nuts. Tree nut allergy reactions can vary from localized reactions, such as itching and tingling of the mouth and lips, to systemic reactions, including anaphylaxis, to potentially no clinical reaction at all.12 These reactions may depend on which protein in different tree nuts are causing the reaction.

Tree nuts comprise different proteins; a person with a tree nut allergy could be reacting to one or more of these proteins. Knowing which protein is causing the reaction is important because different proteins can cause different allergic reactions.

Specific IgE blood testing for tree nut components, currently available for hazelnut, walnut, brazil nut, and cashew, helps your healthcare provider identify the specific proteins that cause your reactions. So instead of knowing that you are allergic to a tree nut in general, you can know exactly which protein may trigger the reaction. Testing with allergen components can also help your healthcare provider determine whether an oral food challenge (OFC) test is recommended. An OFC test can be used to help confirm your tree nut allergy or determine whether you have outgrown it.

Meaning, you can get detailed answers to your tree nut allergy questions. Because it’s not just knowledge you’ll gain, but peace of mind, too.

Create your personalized
symptom assessment.


Tree nut allergy triggers

If you have an allergy to one type of tree nut, you have a higher chance of being allergic to other types of tree nuts, too.5 Plus, cross-contamination between multiple tree nuts is common during manufacturer processing. So, many people with an allergy to one tree nut avoid all tree nuts. 

The most widely eaten kinds of tree nuts include:

  • Almonds
  • Brazil nuts
  • Cashews
  • Hazelnuts (including filberts, a type of hazelnut)
  • Pecans
  • Pine nuts
  • Pistachios
  • Walnuts


Tree nuts can also be a hidden ingredient in many foods—this is why it’s important to read the label or ask about ingredients before buying or eating certain foods. Ingredients in packaged foods can change at any time—and without warning—so carefully check the ingredients every time. 

Tree nuts can be found in many foods and drinks, including:

Because of their frequent use of nuts, Chinese, African, Indian, Thai and Vietnamese restaurants, ice cream parlors and bakeries are considered high-risk for people with a tree nut allergy. Even if you order a tree nut-free item, there is the possibility of cross-contact.

Tree nut oils and butters that contain nut protein should also be avoided. Tree nut oils are sometimes used in suntan lotions, shampoos, bath oils and soaps.  



Cross-reactivity is when the proteins in one food are similar to the proteins in another and your body's immune system sees them as the same. There is a high degree of cross-reactivity between cashew and pistachio and between walnut and pecan. Because of this, some healthcare professionals will advise you to avoid other tree nuts even if you only have a confirmed allergy diagnosis to one.6

Learn more about cross-reactivity > 

Seed nut cross reactivity icons
Peanut allergy stats

My Symptom Profile

The peanut connection

There’s a lot of confusion between peanuts and tree nuts. Even though peanuts have the word “nuts” in their name, they are legumes, not nuts. More than half of tree nut allergic patients report an allergy to peanuts.7-9 And 1 out of 3 peanut allergic patients also report a tree nut allergy.10,11

People with a tree nut allergy also commonly avoid peanuts because of the likelihood of cross-contact or cross-contamination—when one food comes into contact with another food and their proteins mix—during the manufacturing process.

Learn more about peanuts > 

My Symptom Profile

Make the most of your appointment
Talk to your healthcare provider about specific IgE blood testing.

Use these questions to help your healthcare provider understand what’s going on with your symptoms. Review your answers together during your office visit to decide if specific IgE blood testing is right for you.

Help your healthcare provider understand what’s been going on with your symptoms and decide if specific IgE blood testing is right for you!

Start Questionnaire

Here Is Your Recap. Now What?

What can your My Symptom Profile tell you about allergies? Nothing, by itself. So resist the temptation to self-diagnose. Treating allergy symptoms with over-the-counter medications or other remedies without determining the cause could lead to more issues in the long run. When paired with testing, such as specific IgE blood testing for food or respiratory allergies, your My Symptom Profile can guide your healthcare provider in creating a customized trigger-management plan to help reduce exposure to suspected allergens.

What symptoms are you experiencing or have you experienced?

Do your symptoms get worse during a particular time?

Do you notice your symptoms more in certain places?

How long have your symptoms been present?


Select all that apply
Runny nose
Itchy eyes
Chest tightness
Abdominal cramps
Itchy mouth
Difficulty breathing
Red, itchy patches of skin
Scratchy throat
Select all that apply
In the morning
At nighttime
In the fall
In the spring/summer
In winter or when temperatures drop
After eating certain foods
When sick
During or after exercise
Select all that apply
At home
At school/work
Around pets or animals
Select one
Since birth
Less than 1 week
More than 6 weeks
For several years

Download a PDF of your results to help guide your conversation and maximize your time with your healthcare provider.

Download Results
Testing icon

Am I Allergic?

People who have high levels of tree nut antibodies in their blood are most likely to have their allergy for life.2 A simple blood test that measures these antibodies can help your healthcare professional determine whether or not you or your child are likely to outgrow a tree nut allergy. Knowing the true cause of your symptoms now may also help you avoid more serious issues in the future. For example, a food allergy reaction sends someone to the ER every 3 minutes.13

Knowing if you’re allergic, and what you’re allergic to can help you get relief. Be sure to consult with your healthcare professional.

  1. Sicherer SH, Munoz-Furlong A, Godbold JH, Sampson HA. US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up. J Allergy Clin Immunol 2010;125:1322-6. (III).
  2. Grabenhenrich L, et al. Anaphylaxis in children and adolescents: The European Anaphylaxis Registry. J Allergy Clin Immunol 2016;137:1128-37. 
  3. Bock SA, et al. Fatalities due to anaphylactic reactions to foods. J Allergy Clin. Immunol 2001;107:191-3.
  4. Fleischer DM, et al. The natural history of tree nut allergy. J Allergy Clin Immunol, 2005;116(5):1087-1093.
  5. Clark A. and Ewan P. The development and progression of allergy to multiple nuts at different ages. Pediatr Allergy Immunol. 2005;16:507– 11.
  6. Burks AW, Tang M, Sicherer S, Muraro A, Eigenmann PA, Ebisawa M, et al. ICON: food allergy. J Allergy Clin Immunol 2012;129:906-20. (IV).
  7. Maloney J, et al. The use of serum-specific IgE measurements for the diagnosis of peanut, tree nut, and seed allergy. J Allergy Clin Immunol. 2008;122:145-51.
  8. Masthoff L, et al. Peanut allergy is common among hazelnut-sensitized subjects but is not primarily the result of IgE cross-reactivity. Allergy 2015; 70: 265–274.
  9. Eller E, et al. Cor a 14 is the superior serological marker for hazelnut allergy in children, independent of concomitant peanut allergy. Allergy 2016;71:556-62.
  10. Sicherer SH, Burks AW, Sampson HA. Clinical features of acute allergic reac- tions to peanut and tree nuts in children. Pediatrics 1998;102:e6. (III).
  11. Ewan PW. Clinical study of peanut and nut allergy in 62 consecutive patients: new features and associations. BMJ 1996;312:1074-8. (III).
  12. Weinberger T, Sicherer S. Current perspectives on tree nut allergy: a review. J Asthma Allergy. 2018; 11: 41–51.
  13. Clark S, et al. Frequency of US emergency department visits for food-related acute allergic reactions. J Allergy Clin Immunol. 2011; 127(3):682-683.