Hay fever allergy medication is the cornerstone of managing allergic rhinitis, a condition affecting around one in five people in the UK. Whether your symptoms are triggered by grass, tree, or weed pollen, choosing the right treatment — from non-sedating antihistamines and intranasal corticosteroids to eye drops and immunotherapy — can make a significant difference to your quality of life. This guide covers the full range of options available in the UK, including over-the-counter and prescription treatments, how to use them safely and effectively, and when to seek further medical advice.

Understanding Hay Fever and When Medication Is Needed

Hay fever, known clinically as allergic rhinitis, is one of the most common allergic conditions in the UK, affecting approximately 1 in 5 people at some point in their lives (NHS). It occurs when the immune system overreacts to airborne allergens — most commonly grass pollen, tree pollen, or weed pollen — triggering the release of histamine and other inflammatory mediators. This immune response produces the characteristic symptoms of sneezing, nasal congestion, itchy or watery eyes, and an itchy throat or palate.

Symptoms typically follow a seasonal pattern, though timing varies by region and year-to-year weather conditions (UK Met Office pollen calendar). As a general guide, tree pollen season runs from late February to mid-May, grass pollen from mid-May to July, and weed pollen from June to September. Some individuals experience perennial (year-round) allergic rhinitis triggered by indoor allergens such as house dust mites, pet dander, or mould spores. Understanding your specific trigger can help guide the most appropriate hay fever allergy medication.

Medication is generally recommended when symptoms are moderate to severe, persistent, or significantly affecting quality of life, sleep, or daily activities such as work or school. The NHS advises that people with mild, infrequent symptoms may manage adequately with avoidance strategies — such as checking pollen forecasts, wearing wraparound sunglasses, showering after being outdoors, and using saline nasal irrigation to rinse allergens from the nasal passages — but most people with hay fever will benefit from pharmacological treatment during peak pollen periods.

You should seek advice from a GP if:

• Symptoms remain poorly controlled despite appropriate over-the-counter (OTC) treatment

• There is diagnostic uncertainty about the cause of your symptoms

• You have severe unilateral (one-sided) nasal obstruction, recurrent heavy nosebleeds, facial pain or swelling, or persistent purulent nasal discharge

• Hay fever is worsening asthma control

• Occupational rhinitis is suspected

• Immunotherapy is being considered

Seek urgent medical attention if you develop severe breathing difficulty, wheeze, or swelling of the lips, tongue, or throat, as these may indicate a serious allergic reaction.

Types of Hay Fever Medication Available in the UK

A range of hay fever allergy medication is available in the UK, spanning several pharmacological classes. NICE CKS, BSACI, and ARIA guidelines recommend a stepwise approach, beginning with non-sedating antihistamines and intranasal corticosteroids as first-line treatments.

Antihistamines work by blocking H1 histamine receptors, thereby reducing sneezing, itching, and watery eyes. Second-generation antihistamines — including cetirizine, loratadine, and fexofenadine — are preferred because they cause significantly less sedation than older first-generation agents such as chlorphenamine. They are available as tablets and liquid formulations.

Intranasal corticosteroids (INCs) such as beclometasone, fluticasone propionate, and mometasone are considered the most effective single treatment for moderate-to-severe allergic rhinitis, particularly for nasal symptoms. They work by reducing local mucosal inflammation and are most effective when started one to two weeks before the anticipated pollen season. Several preparations are available over the counter at pharmacies.

Eye drops for ocular symptoms fall into two main categories:

• Mast cell stabilisers, such as sodium cromoglicate, work by preventing mast cells from releasing histamine and other inflammatory mediators. They are most effective when used regularly before and throughout the pollen season.

• Antihistamine eye drops, such as azelastine eye drops, act more rapidly and are useful for prompt relief of itching, redness, and watering.

Decongestants (e.g., xylometazoline nasal sprays) may provide short-term relief of nasal congestion but must not be used for more than seven consecutive days due to the risk of rebound congestion (rhinitis medicamentosa). Oral decongestants containing pseudoephedrine carry additional safety considerations (see the side effects section).

Intranasal ipratropium bromide may be considered for patients in whom watery rhinorrhoea (runny nose) is the predominant symptom and has not responded adequately to other treatments.

Saline nasal irrigation (using isotonic or hypertonic saline) is a safe, non-pharmacological adjunct that can help clear allergens and mucus from the nasal passages and is recommended in UK guidance as a complementary measure.

Montelukast (a leukotriene receptor antagonist) is not a first-line treatment for allergic rhinitis. It may be considered in selected patients, particularly those with coexisting asthma, but only under medical supervision. The MHRA issued a safety warning in 2019 regarding neuropsychiatric reactions associated with montelukast, including sleep disturbances, mood changes, and suicidal thoughts. Patients and carers should be made aware of these risks before starting treatment.

Immunotherapy — either subcutaneous (SCIT) or sublingual (SLIT) — is the only treatment that can modify the underlying allergic response. NICE guidance (TA246) supports the use of sublingual grass pollen immunotherapy (e.g., grass pollen allergen extract) for adults with severe grass pollen-induced rhinitis that has not responded adequately to standard pharmacotherapy. NICE Technology Appraisals are required to be funded by the NHS within three months of publication; access is via referral to a specialist allergy or ENT clinic, and local service pathways may vary.

How to Use Antihistamines, Nasal Sprays and Eye Drops Safely

Using hay fever allergy medication correctly is essential to achieving optimal symptom control and minimising the risk of side effects. Each medication class has specific administration guidance that patients should follow carefully.

Antihistamines are generally taken once daily for second-generation agents. They can be taken as needed for mild or intermittent symptoms, or regularly throughout the pollen season for persistent symptoms. Taking them at the same time each day helps maintain consistent effect. Avoid first-generation antihistamines such as chlorphenamine before driving or operating machinery, as they impair alertness (BNF).

Intranasal corticosteroid sprays require correct technique to be effective:

• Prime the spray before first use by actuating it several times until a fine mist appears, and re-prime if it has not been used for several days

• Blow your nose gently before use

• Tilt your head slightly forward, not back

• Direct the nozzle towards the outer wall of the nostril (away from the nasal septum) to reduce the risk of nosebleeds

• Breathe in gently through the nose as you spray

• Avoid sniffing hard immediately after application

• Clean the nozzle regularly according to the product instructions

• If one nostril becomes sore or irritated, alternate nostrils temporarily

If nasal congestion is very severe, a short course of a topical decongestant spray used shortly before the corticosteroid spray may improve delivery. However, the decongestant should not be continued beyond seven days.

These sprays must be used regularly — ideally daily — to build up their anti-inflammatory effect. Patients often discontinue them prematurely, mistakenly believing they are ineffective, when in fact consistent use over one to two weeks is required before full benefit is achieved.

Eye drops should be instilled with clean hands, with the head tilted back and the lower eyelid gently pulled down. For contact lens wearers:

• Preservative-free formulations are preferable where available, as preservatives in some drops may damage soft contact lenses

• If using preserved drops, remove lenses before instillation and wait at least 15 minutes before reinserting them (refer to the individual product's Summary of Product Characteristics for specific guidance)

If symptoms persist or worsen despite correct use, or if any change in vision occurs, seek prompt advice from your GP or an optometrist.

Buying Hay Fever Medication: Pharmacy, Prescription and NHS Options

In the UK, many effective hay fever allergy medications are available without a prescription, making them accessible for self-management. Community pharmacists play a key role in advising patients on appropriate product selection, particularly for those with other medical conditions or who are taking other medicines.

Over-the-counter (OTC) options widely available in UK pharmacies include:

• Cetirizine and loratadine tablets (antihistamines)

• Fluticasone propionate and beclometasone nasal sprays (intranasal corticosteroids); some mometasone furoate nasal spray products are also available OTC

• Fexofenadine 120 mg tablets, which have been reclassified as a pharmacy medicine (P medicine) in the UK and are available OTC for adults and young people aged 12 and over with seasonal allergic rhinitis

• Sodium cromoglicate eye drops (mast cell stabiliser)

• Short-term decongestant nasal sprays

For patients with more severe or complex hay fever, a GP can prescribe treatments including higher-strength or combination products. Azelastine nasal spray remains a prescription-only medicine (POM). Combination products such as azelastine with fluticasone propionate nasal spray are available on prescription for adults and adolescents aged 12 and over. Prescription use of fexofenadine and other agents remains appropriate where clinically indicated.

NHS England guidance (2018) advises that GPs should not routinely prescribe OTC hay fever treatments on the NHS for adults, as these are considered self-care items. Exceptions are based on clinical need — for example, where a patient has a complex condition requiring medical supervision — rather than financial circumstances. Patients who need prescription-only treatments will continue to receive these on the NHS as appropriate.

For those considering immunotherapy, referral to a specialist allergy or ENT clinic is required. NICE guidance (TA246) supports the use of sublingual grass pollen immunotherapy for adults with severe grass pollen-induced rhinitis that has not responded adequately to standard pharmacotherapy. As a NICE Technology Appraisal, this treatment should be funded by the NHS within three months of the guidance publication date; access is through specialist services and local referral pathways.

Patients and healthcare professionals are encouraged to report suspected side effects from any hay fever medication via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk).

Side Effects and Safety Considerations for Allergy Medicines

Whilst hay fever allergy medication is generally well tolerated, all medicines carry the potential for side effects, and certain safety considerations are particularly relevant in specific patient groups.

Antihistamines: Second-generation antihistamines such as cetirizine and loratadine have a low sedation profile, but cetirizine may cause drowsiness in some individuals. Patients should be advised not to drive or operate heavy machinery if they experience this effect (BNF). First-generation antihistamines (e.g., chlorphenamine) are more strongly sedating and have anticholinergic effects; they should be used with caution in elderly patients and in those with urinary retention, glaucoma, or prostatic hypertrophy. Age restrictions and licensed indications vary between products — always check the product's Summary of Product Characteristics (SmPC) or seek pharmacist or GP advice, particularly for children. Most antihistamines are not licensed for use in children under two years of age and should only be used in this age group under medical supervision.

Intranasal corticosteroids: When used at recommended doses, systemic absorption is minimal and clinically significant systemic side effects are uncommon. Local side effects may include:

• Nasal dryness or irritation

• Epistaxis (nosebleeds)

• Rarely, nasal septal perforation with prolonged incorrect use

Children using intranasal corticosteroids long-term should have their height monitored regularly as a precaution, in line with MHRA guidance, as a small effect on growth has been observed with some preparations.

Decongestants: Oral decongestants containing pseudoephedrine should be avoided in patients with hypertension, cardiovascular disease, hyperthyroidism, severe renal impairment, or those taking monoamine oxidase inhibitors (MAOIs). In 2024, the MHRA and the European Medicines Agency's Pharmacovigilance Risk Assessment Committee (PRAC) issued updated safety warnings for pseudoephedrine, highlighting a risk of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). Patients taking pseudoephedrine should stop immediately and seek urgent medical attention if they develop a sudden severe headache, visual disturbances, seizures, or focal neurological symptoms. Topical nasal decongestants (e.g., xylometazoline) must not be used for more than seven days.

Montelukast: If montelukast is prescribed for coexisting asthma or in selected rhinitis patients, patients and carers should be informed of the MHRA's 2019 warning regarding neuropsychiatric reactions, which may include sleep disturbances, nightmares, anxiety, depression, and, rarely, suicidal thoughts. Any such symptoms should be reported to a GP promptly.

Urgent red flags — seek immediate medical attention if you experience:

• Severe breathing difficulty, wheeze, or chest tightness

• Swelling of the lips, tongue, or throat (angioedema)

• Sudden severe headache, visual disturbance, or focal neurological symptoms (particularly if taking pseudoephedrine)

When to seek non-urgent GP advice:

• Symptoms are not controlled despite appropriate OTC treatment

• You develop facial pain, fever, or purulent nasal discharge (suggesting sinusitis)

• You experience significant side effects from medication

• Hay fever is affecting asthma control, as allergic rhinitis and asthma frequently coexist and require integrated management

• You have severe or recurrent nosebleeds

Pregnancy and breastfeeding: Pregnant or breastfeeding women should seek pharmacist or GP advice before starting any hay fever medication. Loratadine and cetirizine are generally considered the preferred oral antihistamines in pregnancy based on available safety data (UKTIS/BUMPS). Intranasal corticosteroids with established safety profiles (e.g., beclometasone, fluticasone propionate) are generally preferred over systemic treatments during pregnancy. Individual product SmPCs and BNF guidance should be consulted.

Suspected side effects from any hay fever medication should be reported via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk).

Frequently Asked Questions