Allergic Rhinitis
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Introduction
ARIA (Allergic Rhinitis and its Impact on Asthma) classification defines allergic rhinitis as seasonal, perennial or intermittent. In addition to increased economic burden, absenteeism and reduced productivity (at work or school), secondary infections, and inappropriate antibiotic use, poor symptom control leads to secondary infections.
Therapeutic Objective
Avoid exposure to allergens to prevent allergic symptoms
Control and suppress allergic symptoms
Ensure medication side effects don't negatively affect daily life activities
Reduce interference with school, work, leisure activities, sleep
Diagnosis
When assessing allergic conditions, a thorough clinical history and physical examination are essential. Here's what to consider:
Symptoms: Pay close attention to symptoms like nasal congestion, itching, runny nose, sneezing, postnasal drip, and eye-related issues.
Duration and Frequency: Determine whether symptoms are intermittent or persistent and the severity.
Triggers: Identify potential allergens such as pollen, animal dander, or other environmental factors.
Personal or Family Allergy History: Check for any family history of allergies or atopic conditions (asthma, eczema).
Other Medical Conditions: Look for co-existing conditions like sleep apnea, snoring, asthma, or conjunctivitis.
Medication History: Some drugs like aspirin (ASA), NSAIDs, or ACE inhibitors may trigger nasal symptoms. Make note of any self-treatment attempts with over-the-counter medications and how effective they were.
Nasal Mucosa: Use an otoscope to examine the nasal passages for color and structural issues.
Facial Signs: Look for allergic shiners (infraorbital edema), redness, swelling in the eyes, or a transverse nasal crease.
Throat: Cobblestone appearance of the posterior oropharynx and visible postnasal drip.
Skin Testing: This is the preferred method to confirm allergic sensitivity and identify specific allergens. It helps guide avoidance measures and confirm the diagnosis. If the patient cannot stop antihistamines or has widespread skin issues, consider serum testing instead.
Important Note: Patients should stop antihistamines (and some antidepressants) at least 3 days before skin testing, unless otherwise discussed.
Serum IgE Testing (ELISA): While more expensive and less sensitive than skin tests, in vitro IgE testing may be used when skin testing isn't feasible. Measuring total IgE isn't generally useful, as it doesn't correlate well with allergies.
Nonpharmacologic Choices
Allergen Avoidance: The most effective strategy for managing allergic rhinitis is avoiding allergens that trigger symptoms:
Pollen: Use air conditioning to minimize exposure by keeping windows closed. Nasal filters can reduce the amount of pollen and allergens entering the nasal passages.
Animal Dander: Removing pets from the home can help alleviate perennial symptoms.
Dust Mites: Use impermeable covers for mattresses and pillows. Although evidence is mixed, some studies show a reduction in emergency room visits for asthma after using these covers.
Pharmacologic Choices
Intranasal Saline Sprays: Helpful for washing out allergens and mucus from the nasal passages.
Antihistamines: Used to alleviate symptoms such as sneezing, rhinorrhea, and nasal itching. Examples include bilastine, cetirizine, desloratadine, and fexofenadine.
Most effective when used prophylactically.
Second-generation antihistamines are preferred as they cause fewer sedative effects compared to first-generation antihistamines.
Decongestants: Help with nasal congestion, but should be used cautiously. Oral pseudoephedrine is generally more effective than phenylephrine.
Leukotriene Receptor Antagonists: Montelukast is an option, particularly for patients with coexisting asthma or nasal polyps.
Intranasal Therapy
Intranasal Corticosteroids (INCS): These are the mainstay of therapy for moderate to severe symptoms. Regular use offers significant relief from nasal congestion and other symptoms.
Combination Therapy: INCS combined with antihistamines (e.g., azelastine/fluticasone) may be useful for patients who do not achieve adequate relief from INCS alone.