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Allergy testing

Hay fever testing and immunotherapy

Identifying which pollens drive your hay fever, and the desensitisation treatments that can change the disease itself.

Key facts

At a glance

  • Testing: skin prick or blood IgE tests identify your pollen triggers - tree pollen in spring, grass in early summer, weeds in late summer.

  • Who should consider immunotherapy: people whose symptoms persist despite proper use of antihistamines and steroid nasal sprays.

  • Treatment: daily tablets under the tongue or a course of injections, started before pollen season and continued for three years.

  • Results: symptom improvement typically appears in the first season, with lasting benefit after a full course.

  • Follow-up: an allergist reviews progress annually and adjusts the plan; immunotherapy is the only treatment that modifies the underlying allergy.

The full picture

What this test involves, and how to get it

Hay fever testing matches your symptom calendar to specific pollens: birch and other trees in spring, grasses from May to July, and weeds late in the season. Skin prick testing gives an answer in twenty minutes; blood IgE tests do the same job when skin testing is impractical. For most people the result fine-tunes standard treatment - knowing your season lets you start steroid nasal sprays two weeks early, which transforms their effectiveness. For the minority whose symptoms remain disruptive despite optimal sprays and antihistamines, testing is the gateway to immunotherapy.

Pollen immunotherapy retrains the immune system with daily under-the-tongue tablets or clinic-based injections, started well before the season and continued for three years. It is the only treatment that changes the allergy itself rather than damping symptoms, and benefits persist after the course ends. NHS immunotherapy is available but concentrated in specialist centres with limited capacity, so waits are common. Private allergy clinics offer testing within days and can initiate sublingual immunotherapy in a single supervised first dose, with the ongoing tablets taken at home - a practical route for exam-season students, outdoor workers and anyone whose summers are being lost to grass pollen.

A quiet reminder

This guide is for information, not medical advice.

Your own clinician knows your history and can tell you which parts apply to you. Next review of this page: 2027-09-27.

Frequently asked

Common questions about Hay fever testing and immunotherapy.

Quick, plain-English answers to what people ask us most.

  • What is hay fever testing and immunotherapy?

    Hay fever testing identifies which specific pollens or other allergens trigger your symptoms, usually through blood tests measuring specific IgE antibodies or skin prick testing. Immunotherapy is a treatment that gradually desensitises your immune system to a confirmed allergen, given as tablets, drops or injections over a course of time.

  • Why would a doctor order hay fever testing?

    It's used when hay fever symptoms are significant, unclear, or not well controlled with standard treatments like antihistamines, to confirm which pollens are responsible and guide more targeted treatment, including whether immunotherapy might help. It's also useful if symptoms overlap with other allergies.

  • Do I need to prepare for testing?

    For blood tests, no special preparation is usually needed. For skin prick testing, you'll typically need to stop antihistamines for around a week beforehand, as they can suppress the skin's reaction; your clinic will confirm exact timing.

  • What happens during the test and immunotherapy?

    Blood testing involves a simple sample from your arm, while skin prick testing involves placing tiny amounts of allergen extracts on your forearm and gently pricking the skin, then checking for a reaction after 15 to 20 minutes. If immunotherapy is recommended, it's typically taken as a daily tablet or occasional injection over a period of months to years, with your allergy specialist monitoring progress.

  • Does testing or immunotherapy hurt or carry risks?

    Skin prick testing can cause brief itching or a small raised bump at the test sites, and blood tests involve a needle prick, both low risk. Immunotherapy carries a small risk of allergic reactions, so it's started and monitored under specialist supervision, particularly the injectable forms.

  • How long do results take?

    Skin prick test results are available the same appointment, within about 20 minutes. Blood test results for specific allergens usually take a few days to a week.

  • What do abnormal results mean, and what happens next?

    A positive result confirms sensitivity to a specific pollen, which helps target treatment, whether that's more effective avoidance measures, optimised medication, or a discussion about immunotherapy if symptoms are severe. Your allergy specialist will explain what the pattern of results means for you specifically.

  • How much does hay fever testing and immunotherapy cost, and is it available on the NHS?

    Both are available on the NHS via allergy services, though access to immunotherapy in particular can be limited and involve a wait. Private testing and treatment are typically available more quickly, with care overseen by a specialist; cost varies by provider.

  • Is hay fever testing accurate and reliable?

    Both skin prick and specific IgE blood testing are well-established, reliable ways of identifying pollen sensitivities when interpreted alongside your symptoms. Occasionally results don't perfectly match reported symptoms, which is why specialist interpretation matters.

  • How do I book hay fever testing and immunotherapy privately, and how quickly can I be seen?

    You can book a private allergy specialist consultation directly, with testing often available at the same visit and immunotherapy planned soon after if suitable.