The best daily allergy medication for you depends on your symptoms, their severity, and whether you have any co-existing conditions such as asthma. Allergic rhinitis and hay fever affect millions of people in the UK, causing sneezing, nasal congestion, itchy eyes, and skin reactions that can significantly disrupt daily life. Fortunately, a range of effective treatments is available — from second-generation antihistamines and intranasal corticosteroids to targeted eye drops — many of which can be obtained over the counter from a UK pharmacy. This guide explains how each option works, what NHS and NICE guidance recommends, and when to seek further advice from your GP.

How Daily Allergy Medications Work

Daily allergy medications work by interrupting the body's immune response to allergens such as pollen, dust mites, pet dander, and mould spores. When the immune system encounters a trigger it has been sensitised to, it releases a chemical called histamine from mast cells. Histamine binds to receptors throughout the body, producing the familiar symptoms of allergic rhinitis and hay fever — sneezing, itching, nasal congestion, watery eyes, and skin reactions.

The most widely used daily allergy medications — antihistamines — work by competitively blocking H1 histamine receptors, preventing histamine from exerting its effects. Second-generation antihistamines such as cetirizine, loratadine, and fexofenadine are preferred in clinical practice because they are largely non-sedating and have a longer duration of action, making them suitable for once-daily dosing.

Other classes of medication target different parts of the inflammatory cascade. Intranasal corticosteroids reduce local mucosal inflammation by suppressing the release of multiple pro-inflammatory mediators, not just histamine. This broader mechanism of action makes them particularly effective for persistent or moderate-to-severe nasal symptoms, and they are recommended as first-line treatment for persistent allergic rhinitis by NICE CKS and ARIA guidance.

Leukotriene receptor antagonists, such as montelukast, block another inflammatory pathway. However, montelukast is not a first-line treatment for allergic rhinitis; it may be considered when other treatments are inadequate or where there is co-existing asthma, and it carries important safety considerations (see Side Effects and Safety Considerations below). It is also worth noting that decongestants — whether oral or topical nasal drops or sprays — are not suitable for daily or prolonged use, as they can cause rebound congestion (rhinitis medicamentosa) and carry additional cardiovascular risks with oral formulations. They should be used for short periods only, typically no more than seven days.

Types of Daily Allergy Medication Available in the UK

In the UK, several categories of daily allergy medication are available, either over the counter (OTC) from pharmacies or on prescription via a GP. Availability and legal classification vary by product, strength, and indication; always check with a pharmacist or consult the relevant Summary of Product Characteristics (SmPC) on the electronic Medicines Compendium (eMC). The main options include:

• Oral antihistamines: Second-generation antihistamines such as cetirizine hydrochloride (10 mg) and loratadine (10 mg) are widely available OTC. Fexofenadine 120 mg is a Pharmacy (P) medicine available without prescription for the relief of seasonal allergic rhinitis (hay fever) in adults and children aged 12 and over; fexofenadine 180 mg is generally a prescription-only medicine (POM) in the UK, licensed primarily for chronic idiopathic urticaria. These antihistamines are suitable for mild-to-moderate allergic rhinitis, urticaria, and hay fever.

• Intranasal corticosteroids (INCs): Preparations such as beclometasone dipropionate (e.g., Beconase), fluticasone propionate (e.g., Flixonase), and mometasone furoate (e.g., Nasonex) are available OTC or on prescription depending on the specific product and indication. They are considered first-line treatment for persistent allergic rhinitis by NICE CKS and ARIA guidance.

• Antihistamine nasal sprays: Azelastine hydrochloride nasal spray acts locally within the nasal passages and has a rapid onset of action. In the UK, azelastine nasal spray is a prescription-only medicine (POM); patients should speak to their GP if they feel this option may be appropriate.

• Antihistamine and mast cell stabiliser eye drops: Sodium cromoglicate eye drops are available OTC and are used for allergic conjunctivitis. Olopatadine eye drops are prescription-only in the UK. Both can be used alongside oral or nasal treatments, but patients should confirm the availability and suitability of specific products with a pharmacist or GP.

• Leukotriene receptor antagonists: Montelukast is available on prescription only and may be considered for patients with co-existing asthma and allergic rhinitis where other treatments have been inadequate. It is not a first-line option for allergic rhinitis alone.

The MHRA and NHS regularly review the safety profiles of these medicines. Notably, the MHRA issued updated guidance in 2020 regarding the potential neuropsychiatric effects of montelukast, advising that patients and carers must be informed of this risk before starting treatment. Product indications and availability vary by brand, strength, and formulation; always seek advice from a pharmacist or GP before starting a new medicine.

Choosing the Right Option: NHS and NICE Guidance

NICE CKS (Allergic rhinitis) and ARIA (Allergic Rhinitis and its Impact on Asthma) guidance recommend a stepwise approach to managing allergic rhinitis. ARIA classifies rhinitis as intermittent (symptoms fewer than four days per week or for fewer than four consecutive weeks) or persistent (symptoms on four or more days per week and for four or more consecutive weeks). Severity is assessed by the impact on daily life, including sleep, work or study, and leisure activities — not by symptom count alone.

For mild, intermittent symptoms, an oral second-generation antihistamine is an appropriate first step. For moderate-to-severe or persistent symptoms, an intranasal corticosteroid is recommended as the preferred first-line treatment, either alone or in combination with an oral antihistamine.

The NHS advises that patients use an intranasal corticosteroid consistently for at least two weeks before assessing its effectiveness, as these medications require regular daily use to achieve their full anti-inflammatory effect. Unlike antihistamines, which can provide relatively rapid symptom relief, intranasal corticosteroids build up their effect over several days of regular use. Correct technique is important: the nozzle should be directed away from the nasal septum (towards the outer wall of the nostril) to reduce the risk of nosebleeds and, with prolonged use, septal damage.

For individuals with both allergic rhinitis and asthma, NICE CKS recommends that both conditions are managed concurrently, as poorly controlled rhinitis can worsen asthma control. In such cases, a leukotriene receptor antagonist may offer dual benefit, though the neuropsychiatric risks of montelukast must be discussed with the patient beforehand.

Pharmacists can provide structured OTC advice and help patients select appropriate treatments without a prescription. If OTC treatments fail to provide adequate control after a reasonable trial period, a GP appointment should be arranged for prescription-strength options or further assessment.

Antihistamines, Nasal Sprays and Eye Drops Compared

Each formulation of daily allergy medication has distinct advantages depending on the predominant symptoms a patient experiences. Understanding these differences helps in selecting the most targeted and effective approach.

Oral antihistamines are convenient, well tolerated, and effective for systemic symptoms including sneezing, itching of the skin, eyes, and throat, and urticaria. However, they are generally less effective than intranasal corticosteroids for nasal congestion, which is driven more by inflammatory oedema than by histamine alone.

Intranasal corticosteroids are the most effective single treatment for nasal symptoms — including congestion, rhinorrhoea, and sneezing — and also have some benefit for ocular symptoms via the nasal-ocular reflex. They are safe for long-term daily use at recommended doses, with minimal systemic absorption when used correctly. To minimise the risk of local side effects such as nosebleeds, the spray nozzle should be aimed away from the nasal septum towards the outer wall of the nostril.

Antihistamine nasal sprays such as azelastine (prescription-only in the UK) have a faster onset than intranasal corticosteroids — within approximately 15 minutes — and are useful for patients who need rapid relief or who experience intermittent symptoms. A combined intranasal corticosteroid and antihistamine spray (Dymista — fluticasone propionate/azelastine) is available on prescription for patients with moderate-to-severe allergic rhinitis who require both mechanisms.

Eye drops are the most targeted option for allergic conjunctivitis. Sodium cromoglicate drops (available OTC) stabilise mast cells and are suitable for regular preventive use, while olopatadine drops (prescription-only in the UK) provide faster symptomatic relief. Using eye drops alongside nasal or oral treatments often provides the most comprehensive symptom control for patients with combined nasal and ocular allergy.

A note on decongestants: Topical nasal decongestants (e.g., xylometazoline) and oral decongestants are not suitable for daily or long-term use. Topical decongestants should not be used for more than seven days, as prolonged use causes rebound congestion (rhinitis medicamentosa). They are not a substitute for the treatments described above.

Side Effects and Safety Considerations

All medications carry the potential for side effects, and daily allergy treatments are no exception. Understanding these risks supports informed decision-making and safe use.

Second-generation antihistamines are generally well tolerated. However:

• Cetirizine is more likely than loratadine or fexofenadine to cause mild sedation in some individuals.

• Dry mouth, headache, and gastrointestinal upset are occasionally reported.

• Fexofenadine is considered the least sedating option and is often preferred for those who drive or operate machinery.

Intranasal corticosteroids, when used at recommended doses, have an excellent safety profile. Potential local side effects include nasal dryness, epistaxis (nosebleeds), and, rarely, nasal septal perforation with prolonged high-dose use or incorrect technique. Systemic absorption is minimal, but patients — particularly children — using intranasal corticosteroids alongside inhaled corticosteroids for asthma should be monitored for cumulative corticosteroid exposure. In children on long-term corticosteroid treatment, growth should be monitored as a precaution.

Montelukast carries an MHRA-mandated warning regarding neuropsychiatric reactions, including sleep disturbances, anxiety, depression, and suicidal ideation (MHRA Drug Safety Update, 2020). Patients and carers must be counselled about these risks before initiation. If any neuropsychiatric symptoms develop, the medication should be stopped promptly and urgent medical advice sought.

Eye drops are generally safe for topical use. Preservative-containing formulations may cause irritation with frequent use; preservative-free alternatives are available for sensitive individuals or those using drops more than four times daily.

Patients should always read the patient information leaflet supplied with their medication and consult a pharmacist or GP if they are pregnant, breastfeeding, or taking other regular medicines, as interactions and contraindications may apply. Any suspected side effect from a medicine should be reported via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk.

When to Seek Further Advice From Your GP

Whilst many people manage their allergy symptoms effectively with OTC treatments, there are circumstances in which it is important to seek further medical advice. Consulting a GP is recommended in the following situations:

• Symptoms are not adequately controlled after a consistent two-to-four-week trial of an appropriate OTC treatment at the correct dose.

• Symptoms are severe or significantly affecting quality of life, including sleep disturbance, impaired concentration, or reduced ability to work or study.

• Symptoms are present year-round (perennial allergic rhinitis), which may suggest sensitivity to indoor allergens such as house dust mites or pet dander, and may warrant further assessment.

• Asthma symptoms worsen alongside nasal allergy symptoms, as both conditions often require coordinated management.

• Unusual or atypical symptoms are present, such as unilateral nasal obstruction, blood-stained or crusting nasal discharge, or persistent loss of smell. These features may indicate an alternative diagnosis and should be assessed promptly; in some cases, urgent ENT referral may be required.

• Children or elderly patients who may require dose adjustments or have additional safety considerations.

If you experience breathing difficulty, throat swelling, or any other signs of a severe allergic reaction (anaphylaxis), call 999 immediately.

A GP can arrange specific IgE blood tests to help identify allergen triggers. Skin prick testing is typically performed in secondary care — a GP can refer to an NHS allergy or ENT clinic when this is indicated. For patients with confirmed allergic rhinitis who have not responded adequately to pharmacological treatment, referral for consideration of allergen immunotherapy (desensitisation) may be appropriate. Immunotherapy is the only treatment that can modify the underlying allergic response rather than simply managing symptoms, and it is available through specialist NHS services for eligible patients.

Frequently Asked Questions