Management Allergen avoidance Aeroallergens THE role of aeroallergen avoidance in the management of allergic rhinitis is controversial . This controversy largely exists because as a strategy , avoidance of offending allergens makes perfect common and theoretical sense , but it is not supported by evidence from several well-designed randomised control trials .
A Cochrane Review and the ARIA 2008 Update concluded that while physical and chemical methods of aeroallergen avoidance and reduction had been successfully demonstrated to reduce measurable levels of allergens , this effect did not correlate with clinical benefit . 14 , 8 Multifaceted avoidance measures may be of benefit to a small subset of patients .
Some practical techniques that may be helpful in reducing levels of aeroallergens are detailed in box 2 . These interventions can be costly and may be of limited clinical benefit , so they should be recommended with caution and consideration of the patient ’ s economic means .
Pet allergens Counselling a patient to remove a beloved pet from the home is a challenging and perhaps unwarranted task . Patients who are allergic to furred pets may benefit from such measures , however , they may encounter allergens on public transport , schools , workplaces and other public places .
The only study to have demonstrated clinical benefit in pet allergen-control measures compared extensive measures ( washing all floors , removing carpet from bedrooms , applying tannic acid , washing bedding , replacing doonas and pillows , using impermeable covers and washing the cat every two weeks ) with an unchanged environment . These onerous measures resulted in a fall of detectable cat allergen to 6.8 % of baseline , and a significant improvement in nasal airflow and symptoms . 15
Pharmacotherapy A broad summary guideline for the pharmacotherapy of allergic rhinitis adapted from the ARIA 2008 Update and the 2017 eTherapeutic Guidelines is presented in table 5 . 8 ,
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This guideline should be interpreted in the context of a patient ’ s symptoms , the frequency of symptoms and the patient ’ s likely compliance with therapy . A list of common agents in each category in use in Australia is presented in table 6 . It is important to note that some of these agents are prohibited by national and international sport anti-doping agencies .
Immunotherapy Given as subcutaneous immunotherapy or as sublingual immunotherapy in increasing doses , allergen immunotherapy aims to ‘ switch off ’ the immune response to the offending allergen ( s ). The allergen extracts used in these treatments are highly potent .
An immunotherapy protocol is initiated on a patient-by-patient
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Table 5 . Pharmacotherapy in allergic rhinitis Intermittent allergic rhinitis Mild
Moderate-severe
Oral H1-antihistamine OR Intranasal antihistamine OR Oral decongestant ( except in children ) OR Intranasal decongestant ( see box 1 , Rhinitis medicamentosa )
Review in 2-4 weeks Persistent allergic rhinitis Mild
Oral H1-antihistamine OR Intranasal antihistamine AND / OR ONE OF Intranasal corticosteroid ( combination nasal sprays are available ) OR Leukotriene receptor antagonist
Review in 2-4 weeks to assess resolution of symptoms . If no improvement , add intranasal corticosteroids if not already started , otherwise add another of the above agents . If no improvement after subsequent review or if the patient exhibits moderate-severe symptoms , escalate treatment to that for persistent moderate-severe AR .
basis by an immunologist and often continued ( for many years ) under the supervision of the
Oral H1-antihistamine OR Intranasal antihistamine AND / OR Intranasal corticosteroid ( combination nasal sprays are available ) OR Oral decongestants OR Leukotriene-receptor antagonist
Review in 2-4 weeks
Moderate-severe
Intranasal corticosteroid
AND ONE OF Oral H1-antihistamine OR Intranasal antihistamine OR Leukotriene receptor antagonist
Review in 2-4 weeks to assess resolution of symptoms , consider some of the possible reasons of failed treatment :
• Nasal obstruction preventing drug delivery
• Concomitant nasal pathology ( eg , polyps , septal deviation )
Initially , increase the dose or frequency of intranasal corticosteroids .
Consider referral to an ENT surgeon if treatment is unsuccessful after three months or if other concerning features develop in the history or examination .
NOTE : Agents listed in general order of preference .
Product
Table 6 . Common medications used in the treatment of allergic rhinitis
Oral antihistamines Second generation ( cetirizine , desloratadine , fexofenadine , loratadine ) First generation ( cyclizine , diphenhydramine , promethazine )
Intranasal antihistamines Azelastine , levocabastine
Intranasal corticosteroids Budesonide , fluticasone , mometasone
Combination intranasal antihistamine and corticosteroids Fluticasone propionate + azelastine
Leukotriene receptor antagonists Montelukast
Intranasal decongestants Oxymetazoline , phenylephrine , tramazoline , xylometazoline
Oral decongestants Pseudoephedrine , phenylephrine
Features
Second-generation oral antihistamines are preferred because of their greater tolerability and their lack of sedation .
Rapidly effective and generally well tolerated . Azelastine may cause somnolence .
Intranasal corticosteroids are the most efficacious agent in the treatment of AR . 8 There is minimal risk of systemic effect . If nasal congestion is the predominant feature , an intranasal corticosteroid should be considered in the first instance .
Per individual agents above .
Inhibits the leukotriene-mediated inflammation seen in AR . Montelukast is as effective as oral H1-antihistamines and inferior to intranasal corticosteroids in the treatment of AR . 8
Do not exceed five ( preferably three ) days of use
These agents play a limited role in the management of AR but may be of benefit in a select group of patients .
patient ’ s GP . Patients , therefore , need to be prepared to commit cont ’ d next page
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Box 2 . Measures aimed at reducing levels of aeroallergens
House dust mites
• Encase bedding in house dustmite impermeable covers
• Wash bedding on a hot cycle ( 55-60 ° C )
• Replace carpets with hard flooring
• Acaricides
• Vacuum cleaners with integrated HEPA filters
Pets
• Remove cat / dog from home
• Keep pets out of main living areas / bedrooms
• HEPA-filter air cleaners
• Wash pet
Box 3 . Managing allergic rhinitis in children
THERE is little difference between the medications and protocols for managing allergic rhinitis in children compared with adults . The exceptions are for intranasal and oral decongestants , all of which should not be used in children under six .
GPs are advised to check the product restrictions — even in children older than six — for some intranasal and oral decongestants . Weighting of differential diagnoses should be modified with age ; allergic rhinitis is common in children , as are foreign bodies . It is not uncommon for a foreign body to remain in the nose for more than four weeks unbeknownst to parents and forgotten by the child .
One of the key elements in the management of children is the effective delivery of intranasal medications . Consider the following :
• Multiple convenient ( and small ) pump sprays are readily available .
• Several different delivery methods may need to be trialled before success is achieved .
• Older children may respond well to education and selfadministration .
• Education of parent and child is crucial to compliance and successful management .
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Online resources
ASCIA . Skin prick testing for the diagnosis of allergic rhinitis . A manual for practitioners http :// bit . ly / 2qUaCDx
AIHW Allergic rhinitis (‘ hay fever ’) in Australia November 2011 http :// bit . ly / 2sVefNY
References
1 . Feng CH , et al . The united allergic airway : connections between allergic rhinitis , asthma , and chronic sinusitis . American Journal of Rhinology & Allergy 2012 ; 26:187-90 .
2 . Australian Bureau of Statistics . National Health Survey : Summary of Results , 2007-2008 . Australian Government , Canberra , 2009 .
3 . AIHW . Allergic rhinitis (‘ hay fever ’) in Australia . Australian Government , Canberra , 2011 .
4 . Mullins RJ , et al . The economic impact of allergic disease in Australia : Not to be sneezed at . ASCIA / Access Economics Report , November 2007 . bit . ly / 1Np3dzK
5 . Bousquet J , et al . Allergic rhinitis and its impact on asthma . Journal of Allergy and Clinical Immunology 2001 ; 108 : S147-334 .
6 . Fokkens WJ . Antigen‐presenting cells in nasal allergy . Allergy 1999 ; 54:1130-41 .
7 . Robbins S , et al . Diseases of the Immune System . In Robbins and Cotran Pathologic Basis of Disease . Saunders / Elsevier , Philadelphia , PA , 2010 .
8 . Bousquet J , et al . Allergic rhinitis and its impact on asthma ( ARIA ) 2008 . Allergy 2008 ; 1 ; 63 ( s86 ): 8- 160 .
9 . Corren J . Allergic rhinitis and asthma : how important is the link ?. Journal of Allergy and Clinical Immunology 1997 ; 99 : S781-86 .
10 . Burgess JA , et al . Childhood allergic rhinitis predicts asthma incidence and persistence to middle age : a longitudinal study . Journal of Allergy and Clinical Immunology 2007 ; 120:863-69 .
11 . Hu W , et al . Allergic rhinitis : Practical management strategies . Australian Family Physician 2008 ; 37:214 .
12 . Myers WA . The nasal crease : A physical sign of allergic rhinitis . Journal of the American Medical Association 1960 ; 174:1204-06 .
13 . Ramey JT , et al . Rhinitis medicamentosa . Journal of Investigational Allergology and Clinical Immunology 2006 ; 16:148 .
14 . Sheikh A , et al . House dust mite avoidance measures for perennial allergic rhinitis : an updated Cochrane systematic review . Allergy 2012 ; 67:158-65 .
15 . Björnsdottir US , et al . The effect of reducing levels of cat allergen ( Fel d 1 ) on clinical symptoms in patients with cat allergy . Annals of Allergy , Asthma & Immunology 2003 ; 91:189-94 .
16 . Therapeutic Guidelines Limited . Allergic rhinitis . In : eTG complete [ online ]. 2015 .
17 . Australasian Society of Clinical Immunology and Allergy . Immunotherapy for treatment of allergy . 2014 [ online ]. bit . ly / 2tBSthq
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