When allergies attack

Donna Cosgrove MPSI reviews the current evidence for the diagnosis and treatment of allergic rhinitis

Introduction

Allergic rhinitis (AR) affects approximately 18.1 per cent of the global population, with prevalence in Europe estimated to range from 1 per cent to 44 per cent.1 The condition imposes a substantial economic burden due to missed school and work days, with avoidable indirect costs estimated at €2,405 per untreated patient annually in a 2014 European Union analysis.2

Despite this impact, AR is often trivialised, and only about 45 per cent of affected individuals seek medical treatment. Among those who do receive treatment, studies suggest that 18-to-48 per cent of symptoms remain inadequately controlled with pharmacotherapy.1

Characteristic AR symptoms include nasal obstruction, rhinorrhoea, sneezing, nasal itching, puffy eyelids, ocular grittiness, and itchy/red eyes, nose, or palate.2,3 In younger patients, common additional symptoms can include irritability, fatigue, sleep disturbance, chronic cough, or epistaxis. Sleep disturbances can be caused by obstructive sleep apnoea in children with AR — this largely improves with treatment.

Repeated nose-rubbing in children may lead to the development of a transverse nasal crease. Although symptoms may improve over time as patients with AR grow older, the condition is unlikely to completely resolve.3

After exposure to an allergen, an IgE mediated inflammatory process is triggered, resulting in AR symptoms. Mast cell degranulation occurs within minutes before a later inflammatory phase (a few hours later) is initiated.2

If symptoms do not really affect the individual’s usual activities this is considered to be mild AR, but when it becomes detrimental to the person’s lifestyle or quality of life, this is on the moderate-to-severe side of the spectrum. Severe symptoms are very troublesome or significantly impact normal daily functioning.

Seasonal symptoms indicate an outdoor allergen, while more constant symptoms indicate an indoor source. Persistent AR (symptoms are present for more than four days a week or longer than four weeks) is likely due to indoor allergen (dust mites, moulds, animal dander) sensitisation, whereas intermittent AR (symptoms lasting less than four days a week, or less than four weeks per episode) is likely due to outdoor allergen (grass, tree, or weed pollen) sensitisation. The severity of the condition depends on pollination periods, geographic area, and degree of urbanisation.2,3

Risk factors linked with AR include:2

• Being born during pollen season.
• Male sex.
• Parental smoking in the first year of life.
• Early antibiotic use.
• Early exposure to indoor allergens.
• Personal or family history of atopy — childhood AR is strongly associated with increased risk of asthma, especially AR from dust mites.

If symptoms persist despite proper use of topical medication, or in particularly severe cases, allergen testing may be performed, eg, the skin prick allergen test or serum allergen-specific IgE test, but these are not routinely done. Given its high prevalence and impact on quality of life, effective management of AR is an important aspect of clinical practice.

Management

AR is managed by avoiding the allergen as much as is practicable and using medication to prevent or control the symptoms.2 If symptoms do not respond to these measures, leukotriene receptor antagonists or allergen immunotherapy may be offered.

Pharmacological treatment for allergic rhinitis

The Allergic Rhinitis and its Impact on Asthma (ARIA) group has developed detailed guidelines for AR management,4 some of which have been incorporated into the current Common Conditions Service Protocol Allergic Rhinitis and Allergic Conjunctivitis.3 The most recent recommendations are summarised below:

For initial treatment of AR, monotherapy with intranasal corticosteroid (INCS) should be prescribed.5

• In patients with AR where monotherapy is unlikely to significantly improve symptoms, intranasal antihistamines (INAH) and INCS are recommended (for individuals age four and over).4
• In adult AR, fluticasone — furoate or propionate — is recommended over other INCS (although this is a conditional recommendation, ie, it may not be appropriate for all patients). A network meta-analysis identified these two types of fluticasone as likely to be the most effective in improving nasal symptoms in seasonal AR. In perennial AR, budesonide was the most effective; however, data are based on one trial only.
• In children and adolescents, evidence for recommending a specific INCS was not available due to insufficient number of studies. Doses in this population (<12 years) may be lower, eg, half, of the adult dose.
• In terms of choice of a combined INAH and INCS product, ARIA recommends the combination of azelastine-fluticasone over olopatadine-mometasone for adults. A network meta-analysis suggested that, compared to olopatadine-mometasone, azelastine-fluticasone is associated with a 23 per cent likelihood of improvement in nasal symptoms in seasonal AR. For ocular symptoms and rhinoconjunctivitis- related quality of life, this probability was 56 per cent. Similar ADR frequencies were reported for each product.
• Either of the combined INAH/INCS options can be used in children with regard to the Summary of Product Characteristics, based on scarce evidence.
• If the side-effect of a bitter taste is experienced with azelastine-fluticasone, the olopatadine-mometasone may be preferred.
• In patients with AR, ARIA does not recommend using a combination of an INCS and an intranasal decongestant — eg, oxymetazoline, xylometazoline, sometimes used to compensate for the slow onset of action of INCS — due to safety concerns. Studies suggest only a minor difference in symptom improvement when comparing the use of INCS alone to the use of INCS with decongestants. There was however a small but significant increased risk in ADRs identified (eg, rhinitis medicamentosa).
• The use of intranasal decongestants should be avoided in children under 12 years old, pregnant women, and the elderly. Intranasal decongestants, in general, should be only used for a maximum of five days, but preferably less.
• In terms of deciding whether to use INCS alone vs INCS/INAH combination products, aspects like adherence, severity, and history of medication use may be useful to consider. Fixed combination products may be favoured in patients who are experiencing more severe symptoms. However, if cost is an issue, INCS may be a better choice. Results of a network meta-analysis indicate similar improvement levels in symptoms

and similar adverse effect levels with both treatments, although INAH/INCS are associated with higher treatment satisfaction and faster onset of action.

• ARIA guidelines suggest that in patients who experience epistaxis secondary to INCS, or with glaucoma, poor adherence, or corticosteroid phobia, INAH may be preferred, although an INAH monotherapy product is not available in Ireland.
• Despite the increased efficacy in symptom control that is seen from a combination of INAH and INCS, a combination of INCS and oral H1 antihistamines does not seem to provide any benefit for symptoms over using an INCS alone.5 It is suggested that the more expensive combination nasal sprays are justified if the symptoms cannot be otherwise controlled.
• Oral H1 antihistamines are effective for many patients with mild-to-moderate AR who prefer oral medication (or with corticosteroid phobia). First-generation oral H1 antihistamines should usually be avoided, however, due to their sedating side-effects.
• An allergen exposure chamber study to investigate the onset of AR medication action found that the azelastine- fluticasone combination nasal spray is the fastest-acting medication, over oral H1 antihistamines or ICNS alone.
• Regular use of medication throughout the season, even on days with minimal symptoms, is recommended.
• If an allergy is suspected, early diagnosis should take place ideally so that patients can identify triggering allergens.

Allergen immunotherapy

Allergen immunotherapy (AIT), a process of desensitisation, is a proven therapeutic option for the treatment of allergic rhinitis.6 Because immunotherapy is more expensive than other medical treatments for AR it should be considered, within a stratified treatment approach, for patients whose symptoms are more severe.7

Immunotherapy involves the gradual introduction of increasing quantities of an allergen over time to reduce immune system sensitivity. The allergen is typically administered subcutaneously at weekly intervals with gradual dose escalation. Oral (sublingual) administration of tablets containing the allergen is another option. A typical reaction (local reaction) is redness and swelling at the injection site immediately, or several hours after the injection.6 Sometimes, systemic reactions like sneezing, nasal congestion, or hives can occur. Allergen tablets have a more favourable safety profile than injections. SLIT can be administered at home after the first dose is administered under the supervision of a physician.

Allergic rhinitis in an Irish paediatric population

A study published in 20232 examined the main allergens and demographic data in Irish children (aged between one and 19, median age nine) in an urban setting over a five-year period (2015- 2019). For about half of the patient sample included, clinical diagnosis of AR was supplemented with positive allergen-specific tests; and for the other half, diagnosis was based on clinical assessment by an experienced paediatric otolaryngologist.

Findings indicated that the most common aeroallergens were house dust mites (44.7 per cent), followed
by grass pollen (29 per cent), dog dander (16 per cent), cat dander (8.5 per cent), and aspergillus/moulds (2 per cent). Half of the population in the study was sensitised to both dust mites and grass pollen. Sixty-three per cent of the population diagnosed with AR after referral to tertiary paediatric otorhinolaryngology in Dublin were male, and a history of atopic disease was common (26 per cent). The number of AR referrals increased over time ? nearly half of all the referrals included were seen in 2019. Some 30 per cent of patients who presented with recurrent epistaxis and who were suspected of also having AR tested positive for an aeroallergen.

Mobile health in management of allergic rhinitis

A study8 collected data from ‘real world evidence’ through a mobile health (mHealth) app from users with AR called MASK-air. App users (n=2871) rated their overall AR symptom severity using a visual analogue scale. Results indicated that:

• Patients do not follow guideline recommendations, and often treat themselves.
• Treatment adherence is poor. Symptoms are treated depending on perceived symptom control, with therapy enhanced if feeling unwell. Interestingly, the study showed that physicians with AR behave in the same way as their patients in patterns of treatment compliance.
• Concomitant use of multiple arbitrary medications does not improve symptom control.
• The INCS/INAH combination of azelastine-fluticasone was reportedly more effective than INCS alone, which were superior to oral antihistamines.

In the recent report of the OECD on Best Practices for Integrating Care to Prevent and Manage Chronic Diseases, this app (MASK-air [Mobile Airways Sentinel network for airway diseases]) has been listed.9 Although MASK-air is not available for use in Ireland, a similar app called Klarify is available.

Summary

AR is a prevalent inflammatory condition associated with significant morbidity and economic burden. Management includes allergen avoidance, pharmacological therapy — primarily intranasal corticosteroids and antihistamines — and allergen immunotherapy in selected cases. AR is one of the most common diseases managed by pharmacists, who play an essential role in the management of pharmacotherapy, counselling, and disease prevention.

References

1.Mask-Air. (2026). Guideline Development Tool. Available at : www.mask-air.com/etd_nasal/10/.

2. Nae A, Heffernan CB, and Colreavy M. (2023). Allergic rhinitis facts from an Irish pediatric population. World Journal of Otorhinolaryngology-Head and Neck Surgery, 9(04), 333-339.

3. Health Service Executive: Clinical Sub-Group to support the delivery of an Expanded Role for Community Pharmacy. (2025). Common Conditions Service Protocol Allergic Rhinitis & Allergic Conjunctivitis (Final) V1.5 26/09/2025. Available at: assets.hse.ie/media/documents/ Common_Conditions_Service_ Protocol_-_Allergic_Rhinitis_and_ Allergic_Conjunctivitis.pdf.

4. Sousa?Pinto B, Bousquet J, Vieira RJ, et al. (2025). Allergic rhinitis and its impact on asthma (ARIA)?EAACI Guidelines 2024-2025 Revision: Part I: Guidelines on Intranasal Treatments. Allergy. Available at: https:// onlinelibrary.wiley.com/doi/10.1111/ all.70131.

5. Klimek L, Bachert C, Pfaar O, et al. (2019). ARIA guideline 2019: Treatment of allergic rhinitis in the German health system. Allergo Journal International, 28(7), 255-276.

6. Bousquet J, Pfaar O, Togias A, et al and ARIA Working Group. (2019). 2019 ARIA Care pathways for allergen immunotherapy. Allergy, 74(11), 2087-2102. Available at: https://pubmed.ncbi.nlm.nih. gov/30955224/.

7. Health Service Executive. (2024). Treatment for allergic rhinitis. Available at: www2.hse.ie/ conditions/allergic-rhinitis/allergic- rhinitis-treatment.

8. Bousquet J, Devillier P, Arnavielhe S, Bedbrook A, Alexis?Alexandre G, Van Eerd M, … & Yorgancioglu A (2018). Treatment of allergic rhinitis using mobile technology with real?world data: the MASK observational pilot study. Allergy, 73(9), 1763-1774.

9. Bousquet J, Sousa-Pinto B, Anto JM, et al (2024). MASK-air: An OECD (Organisation for Economic Co- operation and Development) best practice for public health on integrated care for chronic diseases. The Journal of Allergy and Clinical Immunology: In Practice, 12(8), 2010-2016.