Allergic rhinitis in children is usually diagnosed by reviewing symptoms, medical history, and a physical examination. A clinician asks when symptoms occur, whether they follow exposure to pollen, dust, pets, or mold, and how they affect sleep or school. If the cause is unclear or confirmation would guide care, skin-prick testing or a blood test for allergen-specific IgE may be recommended.
What clues help doctors recognize allergic rhinitis in children?
Doctors begin by looking at the child's symptoms and the pattern in which they occur. Allergic rhinitis, also called hay fever or nasal allergy, causes inflammation inside the nose after exposure to substances that trigger an allergic response. Symptoms may appear during particular seasons or continue throughout the year, depending on the suspected allergen and the child's environment.
According to the Merck Manual Professional Edition, diagnosis is based mainly on the medical history and physical examination, with allergy-specific tests used when needed. Symptoms doctors may ask about include:
- Repeated sneezing.
- A runny or blocked nose.
- Itching inside the nose, eyes, or throat.
- Watery or itchy eyes.
- Symptoms that return during a particular season or after exposure to certain indoor environments.
These symptoms can also occur with conditions other than allergies, so the clinician considers their timing, duration, and associated features rather than relying on a symptom list alone. For example, whether a child experiences symptoms around pets, during pollen seasons, or in a particular room may help identify a possible trigger.
What happens during the medical examination?
The clinician asks the parent or caregiver when the symptoms started, how often they occur, how long they last, and whether anything seems to make them better or worse. They may ask about the child's home and school environments, exposure to animals or dust, previous illnesses, medicines, and family history of allergies or asthma.
According to MedlinePlus, the examination also considers whether symptoms change with the time of day, season, or exposure to possible allergens. A clinician may examine the inside of the nose and look for swelling or other findings that support the suspected diagnosis. Information about sleep, concentration, school attendance, and daily activities can also help show how much the symptoms affect the child.
Parents can help by describing what they have noticed at home. A brief record of symptom dates, possible exposures, and any medicines already used may make it easier to identify a consistent pattern, particularly when a young child cannot clearly explain itching or other discomfort.
When is allergy testing recommended?
Not every child with a typical pattern of allergic rhinitis needs a test. A clinician may diagnose the condition from the history and examination when the findings are clear. Testing may be useful when the cause remains uncertain, symptoms persist despite initial management, or identifying a specific allergen would influence decisions about avoiding exposure or choosing further care.
The American College of Allergy, Asthma & Immunology explains that an allergy specialist may select skin testing, blood testing, or a combination, depending on the child's history and circumstances. Testing is directed toward allergens that plausibly relate to the child's symptoms, such as relevant pollens, dust mites, mold, or animal dander, rather than using an indiscriminate panel of substances.
How does a skin-prick test work?
A skin-prick test checks whether the child's skin reacts to small amounts of selected allergens. A healthcare professional places drops containing the suspected allergens on the skin, commonly on the forearm or back, and gently pricks the surface through each drop. The areas are then observed for a small raised, red bump. Results are generally available within about 15 to 20 minutes.
According to MedlinePlus Medical Tests, a positive skin reaction can indicate sensitivity to the substance being tested. The test is performed in a healthcare setting, where staff can assess reactions and respond to uncommon but potentially serious complications. Temporary itching and redness at the test sites may occur.
Some medicines, including antihistamines, can affect skin-test results. Parents should tell the clinician about all medicines and supplements the child takes and follow the testing team's instructions. They should not stop a prescribed medicine without guidance about whether it needs to be paused and for how long.
When is a blood test for allergies used?
A blood test may be chosen when skin testing is unsuitable or difficult to interpret, including in some children with extensive skin conditions or those who cannot safely pause medicines that interfere with skin testing. The test measures allergen-specific immunoglobulin E (IgE), an antibody associated with allergic responses, in a blood sample.
The American Academy of Pediatrics' HealthyChildren.org explains that specific IgE blood testing can help identify sensitivities to selected allergens. Blood testing requires a blood draw, and results usually take longer than skin-test results. The clinician chooses which allergens to test based on the child's history and suspected exposures.
What do allergy test results mean?
A positive skin or blood test does not automatically prove that a particular substance is causing the child's nasal symptoms. It can show that the child is sensitized to that allergen, meaning the immune system recognizes it. The finding must match the child's symptoms and likely exposure to be clinically meaningful. A result for an allergen the child rarely encounters, for example, may not explain the symptoms.
The American College of Allergy, Asthma & Immunology notes in its testing and diagnosis guidance that allergy-test results must be interpreted alongside the medical history and examination. Clinicians use this combined information to decide whether an allergy explains the symptoms and whether further evaluation is needed. They may reconsider the suspected cause if test results do not fit the child's symptom pattern.
Can other conditions cause similar symptoms?
Yes. Viral respiratory infections, nonallergic rhinitis, and some structural problems affecting the nose can cause symptoms that overlap with allergic rhinitis. The duration of symptoms, associated signs, examination findings, and response to previous care may help the clinician distinguish between these possibilities.
If the diagnosis remains unclear, the clinician may arrange further assessment or refer the child to an allergist. Additional investigations are selected according to the symptoms and examination rather than being routine for every child with a runny or blocked nose. For example, a child with persistent nasal blockage may need assessment for a cause other than allergy.
Does a child's age affect the diagnosis?
Allergy assessment can be performed in children of different ages, but the clinician chooses the testing method to suit the child's circumstances. Skin-prick testing is used infrequently in infants younger than 6 months, according to the American College of Allergy, Asthma & Immunology's guidance on allergy testing in children and infants. In older infants and children, the choice between skin testing and a blood test depends on the suspected allergen, the medical history, skin condition, and medicines being taken.
For younger children who cannot explain what they feel, caregivers' observations become particularly important. Descriptions of recurring sneezing, nose rubbing, eye symptoms, and when these occur can help the clinician understand the pattern without treating any single behaviour as proof of an allergy.
When should parents arrange an assessment?
Arrange a medical appointment if nasal or eye symptoms keep returning, last for a prolonged period, worsen, disturb sleep, interfere with school or play, or are difficult to explain. Seek assessment sooner if symptoms are unusual or accompanied by other concerning features. A clinician can review the child's history, examine them, and decide whether allergy testing or evaluation for another condition is appropriate.
The aim of diagnosis is not only to name the condition but also to determine which factors are relevant to that individual child. An accurate assessment helps families understand possible triggers and gives the healthcare professional a sound basis for discussing appropriate next steps.