Understanding the Hazelnut IgE Level blood test

The Hazelnut IgE Level blood test measures specific IgE antibodies produced by the immune system in response to hazelnut proteins. When IgE antibodies are present at elevated levels, this indicates sensitisation to hazelnuts, meaning the immune system recognises hazelnut as a potential allergen.

This test does not involve food exposure and is therefore safe for individuals with known or suspected nut allergies. It is commonly used alongside clinical history to support diagnosis, assess allergy risk, and guide dietary advice.

Hazelnut allergy may occur on its own or as part of cross-reactivity, particularly in people with pollen allergies (such as birch pollen), where symptoms may be milder and limited to the mouth.

When a Hazelnut IgE Level test is recommended

This test is recommended when hazelnut allergy is suspected based on symptoms, or when clarification is needed following an allergic reaction. It is also useful in people with multiple allergies or unclear triggers.

Symptoms can vary widely, from mild oral itching to severe systemic reactions. Blood testing helps clarify whether hazelnuts are a likely cause.

Testing may be appropriate if you:

• Experience itching or swelling of the lips, mouth, or throat after eating hazelnuts
• Develop hives, rash, or swelling after nut exposure
• Have gastrointestinal symptoms after consuming hazelnuts
• Have asthma symptoms triggered by nut exposure
• Have a known pollen allergy with oral symptoms to nuts
• Have had an unexplained allergic reaction
• Need confirmation before dietary restriction or reintroduction
• Are undergoing broader allergy testing

Benefits of the Hazelnut IgE Level test

• Identifies allergic sensitisation to hazelnuts
  Detects immune response linked to allergy.
• Safe alternative to food challenge testing
  No exposure to allergen required.
• Supports accurate allergy diagnosis
  Helps confirm or rule out hazelnut allergy.
• Guides dietary and lifestyle decisions
  Informs avoidance or specialist referral.
• Useful in complex or multiple allergies
  Helps identify specific triggers.
• Can support risk assessment for reactions
  Higher levels may suggest increased likelihood of symptoms.
• Simple blood test with no preparation required
  No fasting or special preparation needed.
• Provides reassurance and clinical clarity
  Reduces uncertainty around food triggers.

How the test is carried out

We offer two convenient UK-wide testing options:

Clinic-based blood testing

• Choose your nearest UK clinic
• A healthcare professional collects a blood sample
• The sample is analysed in a certified laboratory
• Results are issued once testing is complete

Home or hotel blood collection (+£60)

• A qualified phlebotomist visits your home, workplace, or hotel
• Blood is collected at a time convenient for you
• No clinic visit required
• Available nationwide across the UK

Both options provide the same laboratory accuracy and clinical reliability.

Understanding your Hazelnut IgE Level results

Low or undetectable IgE levels

Low or undetectable Hazelnut-specific IgE suggests no evidence of allergic sensitisation to hazelnuts.

Typical UK reference range:

• Negative: < 0.35 kU/L

This usually indicates a low likelihood of true hazelnut allergy.

Moderate IgE levels

Moderate IgE levels indicate sensitisation, which may or may not cause symptoms. Clinical history is important for interpretation.

Typical UK reference range:

• Low–moderate sensitisation: 0.35 – 3.5 kU/L

Symptoms may be mild or limited to oral allergy syndrome.

High IgE levels

High IgE levels indicate strong sensitisation and a higher likelihood of clinical allergy.

Typical UK reference range:

• High sensitisation: > 3.5 kU/L

This may be associated with more significant allergic reactions and requires clinical correlation.