Allergic rhinitis (hay fever)

What is it?

According to MedlinePlus: allergic rhinitis is a group of nasal symptoms that appear when breathing in sensitising substances such as dust, animal dander and pollen, and it is called hay fever when pollen is the cause. According to MedlinePlus (hay fever topic) it is “a type of allergy triggered by tree, grass and plant pollen”. The NHS describes it as an allergic reaction to pollen.

CDC 2024 figures (United States): seasonal allergies in 25.2% of adults and 20.6% of children under 18; any allergy in 31.7% of adults and 29.5% of children. These are figures for diagnosed seasonal allergy, not for allergic rhinitis alone.

Causes

According to MedlinePlus: the body releases chemicals that cause symptoms on exposure to the allergen. Windborne pollen from trees, grasses and ragweed usually causes hay fever, while flower pollen does not. Pollen counts in the air rise on hot, dry, windy days and fall on cool, rainy days. Allergies often run in families.

According to MedlinePlus (hay fever): trees, grasses and plants release pollen in spring, summer and autumn, and when it enters the nose and throat it triggers the allergic response. According to the NHS, symptoms occur when pollen comes into contact with the mouth, nose, eyes and throat.

Risk factors

This page does not cover a detailed list of risk factors. From this page's sources: allergies in the family (MedlinePlus), and exposure to allergens such as pollen, dust and animal dander.

Symptoms

Rapid symptoms according to MedlinePlus: itching of the nose, mouth, eyes and throat, runny nose, sneezing, watery eyes, and disturbed sense of smell. Later they develop into: nasal congestion, cough, blocked ears, sore throat, dark circles under the eyes, swelling around the eyes, tiredness, irritability and headache.

According to the NHS: sneezing and coughing, runny or blocked nose, itchy, red and watery eyes, itching of the throat, mouth, nose and ears, loss of smell, facial pain, headache, tiredness; symptoms are usually worst from late March to September in the UK (the pollen season is local and varies by country). According to MedlinePlus (hay fever): runny and blocked nose, cough and postnasal drip, itchy eyes, nose and throat, redness and watering, dark circles under the eyes.

How is it diagnosed?

According to MedlinePlus: the provider examines the body and asks about the timing of symptoms and exposure to allergens; “the skin test is the most common way of testing for allergy”. Blood tests (IgE RAST or eosinophil count) are used if a skin test is not possible. MedlinePlus (hay fever) mentions diagnosis by examination and symptoms with skin or blood tests to identify the allergen.

Treatment

The treatment categories usually used are listed here; this is not a prescription. The doctor chooses the plan according to each person's condition; do not change any medicine or dose without a specialist.

Treatment options (chosen with a doctor or pharmacist): avoiding allergens and staying indoors with windows closed during pollen season (MedlinePlus). Medicines include antihistamines (oral, nasal spray or eye drops); MedlinePlus says “corticosteroid nasal sprays are the most effective treatment”; decongestants (maximum of 3 days), leukotriene inhibitors, allergy shots and sublingual immunotherapy.

According to MedlinePlus (hay fever): oral and nasal medicines, sprays, rinsing the nose with distilled or sterile water and salt, and allergy shots to reduce sensitivity to pollen over the long term. According to the NHS, the pharmacist can recommend antihistamine drops, tablets or sprays and steroid sprays, and non-drowsy options are available on request; the doctor may prescribe steroids or refer for immunotherapy (gradual exposure to pollen through an injection or tablet).

Evidence for complementary approaches according to the NCCIH: “relatively good evidence” for the benefit of saline nasal irrigation; some trials suggest that acupuncture may improve some symptoms; evidence for probiotics is inconsistent; butterbur is unconvincing and has safety concerns; and there is no convincing evidence that honey relieves seasonal allergies.

Follow-up

According to the NHS: see your doctor if symptoms get worse or do not improve with pharmacy medicines. According to MedlinePlus: seek review for severe symptoms, failure of earlier treatments or lack of response.

Complications

This page does not cover complications of allergic rhinitis or its relationship with asthma or sinusitis.

Prevention

According to MedlinePlus: avoid pollen by staying indoors with air conditioning during pollen season and keeping windows closed while sleeping and driving. MedlinePlus (hay fever) suggests following pollen counts.

Self-help measures according to the NHS: applying petroleum jelly around the nostrils to trap pollen, wraparound sunglasses, a mask or a wide-brimmed hat, showering and changing clothes after going out, keeping windows and doors closed, cleaning with a vacuum cleaner with a HEPA filter, and pollen filters for the car. It advises avoiding cutting grass, spending too much time outdoors, keeping fresh flowers indoors, smoking and drying clothes outside, and bringing pets indoors. It points to local resources (pollen bulletins) specific to the UK that are not reproduced here.

Living with it

According to MedlinePlus: most symptoms respond to medicines and severe cases may need allergy shots, and some people, especially children, may grow out of the allergy over time.

Common questions