Diagnosis and Tests for Allergic Rhinitis (Hay Fever): How Doctors Confirm It
Written by: Dr.Muhammad Ihsan Ullah, PhD
Medically reviewed by: Dr. Muhammad Mudassar Hassan Bhatti,MD
Last updated on February 07,2026
Clinicial Summary
Many patients ask how allergic rhinitis is diagnosed, and diagnosis is based on symptom patterns combined with targeted allergy testing. Allergic rhinitis is diagnosed by correlating a patient’s symptom history, physical examination, and targeted allergy testing. The primary diagnostic tools include skin prick testing and allergen-specific IgE blood tests, selected based on age, medication use, comorbid conditions, and test availability. In selected or complex cases, additional investigations such as nasal cytology, nasal provocation testing, FeNO measurement, or imaging may be considered.
Patient Summary
If you experience seasonal or year-round sneezing, nasal congestion, or itchy eyes, your healthcare provider may recommend allergy testing to identify the underlying trigger. The skin prick tests and blood testing to detect allergy antibodies are among the available tests. These evaluations, along with your history and exam, play a role in customizing treatment and prevention.
Why Testing Matters
• Identifies any particular allergens to avoid (environmental control)
• Helps to prevent complications, including exacerbations of asthma and sinusitis
• The diagnosis distinguishes allergic rhinitis from infections or non-allergic rhinitis
Diagnostic Workflow for Allergic Rhinitis
- Detailed symptom history and exposure pattern
- Physical examination of nasal passages and eyes
- Selection of appropriate allergy test
- Use of ancillary tests when necessary
- Correlation of results with clinical symptoms These steps outline the most commonly used tests for allergic rhinitis in clinical practice.
Major Tests for Allergic Rhinitis Explained
Skin Prick Test (SPT)
Skin prick testing is the first-line diagnostic test for inhalant allergens such as pollens, dust mites, molds, and pet dander.
In this test a small droplet of standardized allergen extract is placed on the skin (commonly on forearm or on back). The skin is then pricked and examined after 15–20 minutes.
Procedure & preparation:
- Anti-histamine drugs are usually stopped 3–7 days before testing. Steroids being topically used don’t generally affect results but systemic steroids must be discontinued before testing.
- While choosing site for testing, avoid severe eczema sites.
- The test should be performed by trained staff in clinic with emergency care available.
Interpretation of results:
- Positive: wheal (bump) and flare — size compared to histamine (control group).
- Negative control (saline) rules out irritant.
- Sensitivity & specificity: high sensitivity; positive predictive value is best when history matches test.
It is fast, inexpensive, and tests multiple allergens at once with a high sensitivity profile. This test is not suitable for patients with uncontrolled eczema, patients taking antihistamines or any other medications, and patients with a small risk of systemic reaction (rare).
Intradermal Testing
When the skin prick test is negative but clinical concern persists, then intradermal testing is used in which a small volume of diluted allergen is injected into the dermis (usually for venom or medication allergy).It is considered more sensitive than SPT for certain allergens, but on the other hand, its results sometimes have more false positives and have a higher risk of systemic reaction, so it must be used selectively.
Patch Testing
Patch testing is used to detect delayed allergic reactions, particularly when contact allergens such as perfumes, preservatives, or occupational chemicals are suspected.
Specific IgE Blood Tests (sIgE)
Specific IgE blood tests measure allergen-specific IgE antibodies in the bloodstream and are used when skin testing is not feasible.This is an allergy blood test that measures the concentration of allergen-specific IgE antibodies in blood. It is used when:
- The patient is taking antihistamines or can’t stop other medications.
- Patient with severe eczema or dermatographism and is preventing skin testing.
- Young child patients (sometimes preferred).
- Pre-treatment allergy workup if systemic reaction risk is high.
It has the advantage of objective numeric results, safety, and being unaffected by antihistamines, but its sensitivity profile is lower than SPT for some inhalant allergens, as it may detect sensitization without clinical symptoms (false positive).This blood test for allergies is particularly useful when skin testing cannot be performed.
Total IgE
In order to diagnose immunological problems, parasite infections, and allergic reactions, a total IgE test counts all of the IgE antibodies in your blood. A patient needs a particular IgE test to determine which allergens he is allergic to because this test is not specific. After a healthcare professional draws a blood sample, a laboratory determines the overall amount of IgE antibodies present in that particular blood.Total IgE testing alone is not sufficient to diagnose allergic rhinitis and must be interpreted alongside clinical findings.
Component-Resolved Diagnostics (CRD)
This is an advanced blood test that measures IgE to specific allergen components (molecular allergens) rather than whole extracts.
Component-Resolved Diagnostics (CRD) helps risk stratify for systemic reactions by differentiating between actual sensitization and cross-reactivity (e.g., pollen-related food allergy vs. true food allergy).
Nasal Cytology and Nasal Smear
In this test scraping or lavage of nasal mucosa is examined for eosinophils and neutrophils under microscope.
Clinically:
- Eosinophilia supports allergic inflammation (NARES).
- Helps differentiate allergic vs infectious or nonallergic rhinitis.
Nasal Provocation Test (NPT)
In this test controlled exposure of a suspected allergen is directed into the nasal cavity to document allergic response (sneezing, congestion, objective airflow measures).
This test is employed for research, occupational allergy confirmation, food-related nasal symptoms, and when skin/blood tests are equivocal.
It has limitations, as it requires a clinic setting with monitoring and must be used selectively.
Fractional Exhaled Nitric Oxide (FeNO)
An increased FeNO supports the allergy phenotype and indicates type-2 eosinophilic inflammation.FeNO testing may support allergic inflammation, particularly when allergic rhinitis overlaps with asthma.
Imaging and ENT Evaluation
Nasal endoscopy and sinus CT are recommended in cases of persistent sinus symptoms, probable sinusitis, and structural problems (polyps, septal deviation).
Skin Tests vs Blood Tests: Comparison Table
Feature | Skin Prick Test (SPT) | Specific IgE Blood Test |
Primary use | Detects immediate IgE-mediated sensitization | Detects specific IgE antibodies in blood |
Speed | Shows results in just 15–20 minutes | Shows results in days |
Sensitivity | Higher for inhalant allergens | Variable (slightly lower for some inhalants) |
Specificity | Good when correlated with history | May yield false positives |
Medication Interactions | Antihistamine drugs show interaction | Not affected by antihistamines |
Safety | Smaller risk of systemic reactions (performed under supervision) | Very safe (Supervision not required |
Pediatric Considerations in Allergy Testing
• Many childhood allergies manifest as eczema and nasal symptoms; cooperation and skin condition must be taken into account while developing a testing approach. When SPT is impractical due to severe dermatitis or in babies, blood tests are recommended.If a child has rhinitis and a potential food allergy, refer them to a pediatric allergist for a combined evaluation
Safety, Risks, and Pre-test Instructions
Pre-test: Antihistamines and antidepressants should be discontinued before the start of the test, while intranasal steroids can be continued. Testing should be avoided during acute infections.
During the test: During the test, the clinic settings must have emergency kits, including epinephrine injections; most reactions occur locally, while there are rare chances of systemic reactions.
When to Refer to a Specialist (Allergist/Immunologist/ENT)
The patient should refer to an allergist/immunologist or ENT specialist if:
• Persistent or severe symptoms occur despite therapy.
• Suspected occupational allergy.
• Unclear diagnosis after initial testing.
• Consideration of immunotherapy.
• Recurrent anaphylaxis or severe drug/food allergy history.
• Complex comorbid asthma or sinus disease.
Common Clinical Pitfalls in Diagnosing Allergic Rhinitis
Following are the most common clinical pitfalls:
- Over-reliance on test positivity without symptom correlation.
- Failure to stop antihistamines before skin testing.
- Misinterpretation of cross-reactivity; for example, pollen vs food pollen-related allergy.
- Using total IgE alone to diagnose atopy.
Medical Review Disclaimer
This article is for informational and educational purposes only and does not constitute medical advice. The content is written by a qualified healthcare professional and medically reviewed for accuracy. However, it should not be used as a substitute for professional medical diagnosis, treatment, or advice. Always consult a licensed healthcare provider regarding any medical condition or health concern.
Frequently Asked Questions (FAQs)
- How is allergic rhinitis diagnosed?
Allergic rhinitis is diagnosed based on symptom history, physical examination, and allergy tests such as skin prick tests or specific IgE blood tests. - What is the most common test for allergic rhinitis?
Skin prick testing is the most commonly used test to detect IgE-mediated sensitization to pollens, dust mites, molds, and pet dander. - When are blood tests used instead of skin tests?
Specific IgE blood tests are used when skin testing is not possible, such as in patients on antihistamines, with severe eczema, or in very young children. - Do I need to stop medicines before allergy testing?
Oral antihistamines are usually stopped several days before skin testing, while intranasal steroids can often be continued. Always follow your doctor’s instructions. - When should I see an allergy specialist for testing?
You should see a specialist if symptoms are severe or persistent, diagnosis is unclear, asthma is present, or immunotherapy is being considered.