Allergic rhinitis is seasonal or perennial itching, sneezing, rhinorrhea, nasal congestion, and sometimes conjunctivitis, caused by exposure to pollens or other allergens. Diagnosis is by history and occasionally skin testing. First-line treatment is with a nasal corticosteroid (with or without an oral or a nasal antihistamine) or with an oral antihistamine plus an oral decongestant.
Allergic rhinitis may occur seasonally or throughout the year (as a form of perennial rhinitis). Seasonal rhinitis is usually allergic. At least 25% of perennial rhinitis is nonallergic.
Seasonal allergic rhinitis (hay fever) is most often caused by plant allergens, which vary by season. Common plant allergens include
Causes also differ by region, and seasonal allergic rhinitis is occasionally caused by airborne fungal spores.
Perennial rhinitis is caused by year-round exposure to indoor inhaled allergens (eg, dust mites, cockroaches, animal dander) or by strong reactivity to plant pollens in sequential seasons.
Allergic rhinitis and asthma frequently coexist; whether rhinitis and asthma result from the same allergic process (one-airway hypothesis) or rhinitis is a discrete asthma trigger is unclear.
The numerous nonallergic forms of perennial rhinitis include infectious, vasomotor, drug-induced (eg, aspirin- or NSAID-induced), and atrophic rhinitis (see Rhinitis).
Symptoms and Signs
Patients have itching (in the nose, eyes, or mouth), sneezing, rhinorrhea, and nasal and sinus obstruction. Sinus obstruction may cause frontal headaches; sinusitis is a frequent complication. Coughing and wheezing may also occur, especially if asthma is also present.
The most prominent feature of perennial rhinitis is chronic nasal obstruction, which, in children, can lead to chronic otitis media; symptoms vary in severity throughout the year. Itching is less prominent than in seasonal rhinitis.
Signs include edematous, bluish-red nasal turbinates, and, in some cases of seasonal allergic rhinitis, conjunctival injection and eyelid edema.
Allergic rhinitis can almost always be diagnosed based on history alone. Diagnostic testing is not routinely needed unless patients do not improve when treated empirically; for such patients, skin tests (see Specific tests) are done to identify a reaction to pollens (seasonal) or to dust mite, cockroach, animal dander, mold, or other antigens (perennial), which can be used to guide additional treatment. Occasionally, skin test results are equivocal, or testing cannot be done (eg, because patients are taking drugs that interfere with results); then, RAST (see Specific tests) is done. Eosinophilia detected on nasal smear plus negative skin tests suggests aspirin sensitivity or nonallergic rhinitis with eosinophilia (NARES).
Diagnosis of nonallergic perennial rhinitis is usually also based on history. Lack of a clinical response to treatment for assumed allergic rhinitis and negative results on skin tests and/or RAST also suggest a nonallergic cause.
Treatment of seasonal and perennial allergic rhinitis is generally the same, although attempts at environmental control (eg, eliminating dust mites and cockroaches—see Prevention) are recommended for perennial rhinitis.
The most effective first-line drug treatments are
Less effective alternatives include nasal mast cell stabilizers (eg, cromolyn) given bid to qid, the nasal H1 blocker azelastine 2 puffs once/day, and nasal ipratropium 0.03% 2 puffs q 4 to 6 h, which relieves rhinorrhea. Nasal drugs are often preferred to oral drugs because less of the drug is absorbed systemically.
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Intranasal saline, often forgotten, helps mobilize thick nasal secretions and hydrate nasal mucous membranes; various saline solution kits and irrigation devices (eg, squeeze bottles, bulb syringes) are available OTC, or patients can make their own solutions.
Desensitization immunotherapy may be more effective for seasonal than for perennial allergic rhinitis; it is indicated when
First attempts at desensitization should begin soon after the pollen season ends to prepare for the next season; adverse reactions increase when desensitization is started during the pollen season because the person's allergic immunity is already maximally stimulated.
Montelukast, a leukotriene blocker, relieves allergic rhinitis symptoms, but its role relative to other treatments is uncertain. Omalizumab, an anti-IgE antibody, is under study for treatment of allergic rhinitis but will probably have a limited role because less expensive, effective alternatives are available.
Treatment of NARES is nasal corticosteroids. Treatment of aspirin sensitivity is avoidance of aspirin and nonselective NSAIDs (which can cross-react with aspirin), plus desensitization and leukotriene blockers as needed.
Last full review/revision July 2012 by Peter J. Delves, PhD
Content last modified July 2012