Medical Test Guide for Patients: What the Test Is, How It Is Performed, What Your Results Mean, and Possible Risks
This blood test measures whether your immune system releases histamine when exposed to barley, helping diagnose barley allergy.
{"The test checks if your blood reacts to barley by releasing histamine","It helps diagnose barley allergy or sensitivity","A small blood sample is taken and mixed with barley extract","Results show if you have an allergic reaction to barley","No special preparation is needed before the test"}
Key facts at a glance
- LOINC
- 7115-9
- Short code
- BARHR
- Synonyms
- Barley BasoBnd Ab Qn
- Category
- chemistry
- Sample
- whole-blood
- Container
- EDTA (lavender-top) or sodium heparin (green-top) tube for whole blood basophil histamine release testing
- Units
- N/A
- Ref low
- 10
- Ref high
- 20
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Basophil histamine release assay (flow cytometry or fluorometric immunoassay)
- CPT
- 86003
- SNOMED
- 415689003
- Specimen volume
- 5-10 mL of whole blood
- Stability
- Specimen should be processed within 4-6 hours of collection; keep at room temperature (18-25°C); do not refrigerate or freeze
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 48–168 hours
- Order
- routine
This test is a laboratory procedure that helps your doctor evaluate your overall health, screen for certain conditions, monitor an ongoing illness, or check how well a treatment is working. Your provider may order it during a routine checkup or when you have symptoms that need a closer look.
The barley histamine release test is a blood test that measures whether your immune system reacts to barley by releasing histamine. Histamine is a chemical that your body releases during an allergic reaction. This test is used to determine if you have an allergy or sensitivity to barley.
The test is usually performed in a clinic, hospital, or laboratory. A trained healthcare professional will collect a small sample, such as blood, urine, or a swab, using standard sterile techniques. The process is typically quick, and you can usually return to your normal activities right afterward.
A healthcare professional will draw a small sample of blood from your arm using a needle. The blood sample is then sent to a laboratory where it is mixed with barley extract. If you have antibodies against barley in your blood, they will trigger the release of histamine. The laboratory then measures the amount of histamine released.
Your results are compared with established reference ranges to show whether your values fall within expected limits. Normal results generally suggest no detectable abnormality, while abnormal values may point to a condition that needs further evaluation. Your doctor will explain what the numbers mean for your specific situation and recommend any next steps.
If the test shows high levels of histamine release, it indicates that you may have a barley allergy or sensitivity. Your healthcare provider will interpret the results along with your symptoms and medical history to make a proper diagnosis.
For most patients, this test carries very few risks. You may experience slight discomfort, minor bruising, or a small amount of bleeding at the sample collection site, which typically resolves on its own within a few days. Serious complications are rare, but contact your provider if you notice persistent pain, swelling, or signs of infection.
The risks associated with this test are minimal and similar to any routine blood test. You may experience slight pain or bruising at the needle site, and in rare cases, infection or excessive bleeding may occur.
Reference range
Negative: <10% histamine release; Equivocal: 10-20% histamine release; Positive: >20% histamine releaseN/A
No special preparation required. Patient should inform clinician of all medications including antihistamines, as these may affect results. Discontinue antihistamines for 5-7 days prior to testing if clinically feasible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used to diagnose barley allergy, which can cause symptoms such as skin rashes, digestive problems, respiratory issues, or in severe cases, anaphylaxis. It may also be useful in evaluating patients with unexplained allergic symptoms when barley is suspected as a potential trigger. The test helps distinguish between true allergic reactions and other types of sensitivities.
Frequently asked questions
Do I need to fast before this test?
Can I take antihistamines before the test?
How long does it take to get results?
What should I do if I test positive for barley allergy?
Sources
- 1
- 2
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 15, 2026. · Read our editorial policy