Table of ContentsView AllTable of ContentsHazelnut UsesSymptomsCauses and Risk FactorsDiagnostic TestsTreatmentFrequently Asked Questions

Table of ContentsView All

View All

Table of Contents

Hazelnut Uses

Symptoms

Causes and Risk Factors

Diagnostic Tests

Treatment

Frequently Asked Questions

Tree nuts are nuts that grow on trees. They include Brazil nuts, cashews, walnuts, pecans, pistachios, andhazelnuts. Hazelnut allergy is one of the most common tree nut allergies, affecting 0.2% to 0.5% of people in the United States.

This article explains where hazelnuts are found and what kinds of symptoms an allergic reaction can cause. It will also discuss how hazelnut allergy is diagnosed and how you can manage it if you have this allergy.

Where Hazelnuts Are Found

Hazelnuts can grow almost anywhere in the continental United States.

You’ll find hazelnuts:

Tree Nut Allergy Diet Guide

Hazelnut Allergy Symptoms

With a hazelnut allergy, symptoms typically occur shortly after or immediately after consuming hazelnuts or foods containing them.

Possible reactions, from least severe to most severe, include:

AnaphylaxisAnaphylaxisis a severe, life-threatening allergic reaction that comes on suddenly, making it hard to breathe and potentially causing the body to go into shock. Allergies to tree nuts are among those that are commonly associated with anaphylaxis.Anaphylaxis is a medical emergency.

Anaphylaxis

Anaphylaxisis a severe, life-threatening allergic reaction that comes on suddenly, making it hard to breathe and potentially causing the body to go into shock. Allergies to tree nuts are among those that are commonly associated with anaphylaxis.Anaphylaxis is a medical emergency.

Tree nut allergies typically start in childhood. People with a family history of allergies are at higher risk of developing a tree nut allergy. Tree nut allergies are also associated with eczema and asthma.

These allergic reactions occur when the body’s immune system reacts to the hazelnuts as if they are a harmful substance. This immune response produces the symptoms.

Oral Allergy Syndrome

One type of allergic reaction,oral allergy syndrome (OAS), also called pollen food allergy syndrome, is a form of food allergy in which people who are sensitive to specific types of pollen also react to certain foods that are related to those pollens.

Many people with birch pollen allergies also react to hazelnuts. The pollen from birch trees contains allergens that are similar to substances in hazelnuts, so the body reacts to both.

Symptoms of hazelnut oral allergy syndrome are usually fairly mild and are confined to:

Occasionally, some people with OAS have more severe reactions that may include:

Anaphylaxis is very rare in people with OAS.

Peanuts are not tree nuts. They grow underground and are legumes. Approximately 25% to 40% of people who have a peanut allergy are also allergic to at least one type of tree nut.

In order to diagnose a hazelnut allergy,an allergistwill take a medical history and ask about the timing of your symptoms. They will also ask you if you or your family members have any other allergies.

The allergist will likely perform a skin prick test.

A blood test can detect the presence ofimmunoglobulin E (IgE), an antibody that binds to allergens and triggers the release of chemicals that cause symptoms.

Interpreting Results

An IgE blood test that detects higher-than-normal levels of IgE indicates an allergy, but it does not identify what the allergen is.

During a skin prick test, a small amount of the allergen found in hazelnuts is applied under the surface of your skin. If you develop hives (also called wheals) or another reaction, this could indicate an allergy to hazelnuts. A skin test reaction of 3 mm wheal (hive) larger than the negative control is considered to be positive, which means that you are probably allergic to the substance that was injected. The size of the skin test reaction does not correlate with the severity of the clinical reaction

If those tests are inconclusive, your allergist may recommend an oral food challenge.During this test, you would eat tiny amounts of the food in increasing doses over a period of time. This must be done under supervision in an allergist’s office because there’s a risk of a severe reaction.

The Difference Between Blood Tests and Skin Tests for Allergies

Treating Hazelnut Allergy

Symptoms of OAS may be treated with an over-the-counter antihistamine such as Benadryl.

There is no cure for hazelnut allergy. The only way to avoid a reaction is to avoid eating hazelnuts.

A hazelnut allergy warning on an ingredient label should look like this: “Contains Nuts (hazelnuts).”

Managing Your Food Allergy

Summary

Hazelnut allergy is one of the most common tree nut allergies. This nut is commonly used in cookies, chocolates, and pastries.

With oral allergy syndrome, which causes people who are allergic to pollen to react to other substances (like hazelnuts), reactions are typically mild. However, for people who are specifically highly sensitive to the allergen in hazelnuts, there is a risk of more severe reactions, including anaphylaxis, which is a medical emergency. An allergist can perform a variety of tests to confirm a diagnosis of hazelnut allergy.

A Word From Verywell

Hazelnuts are an ingredient in many foods and desserts. Talk to your healthcare provider or allergist if you notice any symptoms after eating or touching hazelnuts. You may need allergy testing to determine whether you are allergic to hazelnuts and also whether you have allergies to other nuts.

Frequently Asked QuestionsTree nut allergies usually persist throughout a person’s life. However, approximately 10% of those who are allergic to tree nuts may outgrow the allergy over time.You need to avoid anything you know contains actual hazelnuts. Some hazelnut-flavored products, such as coffee, may not contain the hazelnut allergen.To be on the safe side, you should always ask your server or contact the manufacturer to find out for sure.Approximately 25% to 40% of people who are allergic to peanuts are also allergic to at least one type of tree nut.The best way to find out if you are allergic to hazelnuts is to be tested for the allergy.In general, coffee and other hazelnut-flavored products do not contain the hazelnut allergen, but the only way to make sure is to contact the manufacturer.

Tree nut allergies usually persist throughout a person’s life. However, approximately 10% of those who are allergic to tree nuts may outgrow the allergy over time.

You need to avoid anything you know contains actual hazelnuts. Some hazelnut-flavored products, such as coffee, may not contain the hazelnut allergen.To be on the safe side, you should always ask your server or contact the manufacturer to find out for sure.

Approximately 25% to 40% of people who are allergic to peanuts are also allergic to at least one type of tree nut.The best way to find out if you are allergic to hazelnuts is to be tested for the allergy.

In general, coffee and other hazelnut-flavored products do not contain the hazelnut allergen, but the only way to make sure is to contact the manufacturer.

Living With a Food Allergy

10 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Calamelli E, Trozzo A, Di Blasi E, Serra L, Bottau P.Hazelnut allergy.Medicina. 2021; 57(1):67. doi:10.3390/medicina57010067Lomas JM, Järvinen KM.Managing nut-induced anaphylaxis: challenges and solutions.J Asthma Allergy. 2015;8:115–123. doi:10.2147/JAA.S89121American College of Allergy, Asthma & Immunology.Tree nut.Muluk NB, Cingi C.Oral allergy syndrome.Am J Rhinol Allergy. 2018;32(1):27-30. doi:10.2500/ajra.2018.32.4489Geroldinger-Simic M, Zelniker T, Aberer W, et al.Birch pollen-related food allergy: clinical aspects and the role of allergen-specific IgE and IgG4 antibodies.J Allergy Clin Immunol. 2011;127(3):616-22.e1. doi:10.1016/j.jaci.2010.10.027MedlinePlus.Allergy blood test.American Academy of Allergy, Asthma & Immunology.Food allergy.Brown JC.Epinephrine, auto-injectors, and anaphylaxis: challenges of dose, depth, and device.Ann Allergy Asthma Immunol. 2018;121(1):53-60. doi:10.1016/j.anai.2018.05.001American Academy of Allergy, Asthma & Immunology.Everything you need to know about tree nut allergy.American Academy of Allergy, Asthma & Immunology.Hazelnut in hazelnut syrup.Additional ReadingGuidelines for the diagnosis and management of food allergy in the United States: Report of the NIAID-Sponsored Expert Panel.J Allergy Clin Immunol. 2010;126(6 Suppl):S1-S58. doi:10.1016/j.jaci.2010.10.007Webber CM, England RW.Oral allergy syndrome: a clinical, diagnostic, and therapeutic challenge.Ann Allergy Asthma Immunol. 2010;104(2):101-117. doi:10.1016/j.anai.2009.11.007

10 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Calamelli E, Trozzo A, Di Blasi E, Serra L, Bottau P.Hazelnut allergy.Medicina. 2021; 57(1):67. doi:10.3390/medicina57010067Lomas JM, Järvinen KM.Managing nut-induced anaphylaxis: challenges and solutions.J Asthma Allergy. 2015;8:115–123. doi:10.2147/JAA.S89121American College of Allergy, Asthma & Immunology.Tree nut.Muluk NB, Cingi C.Oral allergy syndrome.Am J Rhinol Allergy. 2018;32(1):27-30. doi:10.2500/ajra.2018.32.4489Geroldinger-Simic M, Zelniker T, Aberer W, et al.Birch pollen-related food allergy: clinical aspects and the role of allergen-specific IgE and IgG4 antibodies.J Allergy Clin Immunol. 2011;127(3):616-22.e1. doi:10.1016/j.jaci.2010.10.027MedlinePlus.Allergy blood test.American Academy of Allergy, Asthma & Immunology.Food allergy.Brown JC.Epinephrine, auto-injectors, and anaphylaxis: challenges of dose, depth, and device.Ann Allergy Asthma Immunol. 2018;121(1):53-60. doi:10.1016/j.anai.2018.05.001American Academy of Allergy, Asthma & Immunology.Everything you need to know about tree nut allergy.American Academy of Allergy, Asthma & Immunology.Hazelnut in hazelnut syrup.Additional ReadingGuidelines for the diagnosis and management of food allergy in the United States: Report of the NIAID-Sponsored Expert Panel.J Allergy Clin Immunol. 2010;126(6 Suppl):S1-S58. doi:10.1016/j.jaci.2010.10.007Webber CM, England RW.Oral allergy syndrome: a clinical, diagnostic, and therapeutic challenge.Ann Allergy Asthma Immunol. 2010;104(2):101-117. doi:10.1016/j.anai.2009.11.007

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Calamelli E, Trozzo A, Di Blasi E, Serra L, Bottau P.Hazelnut allergy.Medicina. 2021; 57(1):67. doi:10.3390/medicina57010067Lomas JM, Järvinen KM.Managing nut-induced anaphylaxis: challenges and solutions.J Asthma Allergy. 2015;8:115–123. doi:10.2147/JAA.S89121American College of Allergy, Asthma & Immunology.Tree nut.Muluk NB, Cingi C.Oral allergy syndrome.Am J Rhinol Allergy. 2018;32(1):27-30. doi:10.2500/ajra.2018.32.4489Geroldinger-Simic M, Zelniker T, Aberer W, et al.Birch pollen-related food allergy: clinical aspects and the role of allergen-specific IgE and IgG4 antibodies.J Allergy Clin Immunol. 2011;127(3):616-22.e1. doi:10.1016/j.jaci.2010.10.027MedlinePlus.Allergy blood test.American Academy of Allergy, Asthma & Immunology.Food allergy.Brown JC.Epinephrine, auto-injectors, and anaphylaxis: challenges of dose, depth, and device.Ann Allergy Asthma Immunol. 2018;121(1):53-60. doi:10.1016/j.anai.2018.05.001American Academy of Allergy, Asthma & Immunology.Everything you need to know about tree nut allergy.American Academy of Allergy, Asthma & Immunology.Hazelnut in hazelnut syrup.

Calamelli E, Trozzo A, Di Blasi E, Serra L, Bottau P.Hazelnut allergy.Medicina. 2021; 57(1):67. doi:10.3390/medicina57010067

Lomas JM, Järvinen KM.Managing nut-induced anaphylaxis: challenges and solutions.J Asthma Allergy. 2015;8:115–123. doi:10.2147/JAA.S89121

American College of Allergy, Asthma & Immunology.Tree nut.

Muluk NB, Cingi C.Oral allergy syndrome.Am J Rhinol Allergy. 2018;32(1):27-30. doi:10.2500/ajra.2018.32.4489

Geroldinger-Simic M, Zelniker T, Aberer W, et al.Birch pollen-related food allergy: clinical aspects and the role of allergen-specific IgE and IgG4 antibodies.J Allergy Clin Immunol. 2011;127(3):616-22.e1. doi:10.1016/j.jaci.2010.10.027

MedlinePlus.Allergy blood test.

American Academy of Allergy, Asthma & Immunology.Food allergy.

Brown JC.Epinephrine, auto-injectors, and anaphylaxis: challenges of dose, depth, and device.Ann Allergy Asthma Immunol. 2018;121(1):53-60. doi:10.1016/j.anai.2018.05.001

American Academy of Allergy, Asthma & Immunology.Everything you need to know about tree nut allergy.

American Academy of Allergy, Asthma & Immunology.Hazelnut in hazelnut syrup.

Guidelines for the diagnosis and management of food allergy in the United States: Report of the NIAID-Sponsored Expert Panel.J Allergy Clin Immunol. 2010;126(6 Suppl):S1-S58. doi:10.1016/j.jaci.2010.10.007Webber CM, England RW.Oral allergy syndrome: a clinical, diagnostic, and therapeutic challenge.Ann Allergy Asthma Immunol. 2010;104(2):101-117. doi:10.1016/j.anai.2009.11.007

Guidelines for the diagnosis and management of food allergy in the United States: Report of the NIAID-Sponsored Expert Panel.J Allergy Clin Immunol. 2010;126(6 Suppl):S1-S58. doi:10.1016/j.jaci.2010.10.007

Webber CM, England RW.Oral allergy syndrome: a clinical, diagnostic, and therapeutic challenge.Ann Allergy Asthma Immunol. 2010;104(2):101-117. doi:10.1016/j.anai.2009.11.007

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