ALLERGIC RHINITIS


I. Diagnosis
  1. Clinical
    1. Typical symptoms of clear rhinorrhea, sneezing, and/or eye irritation; occasionally cough triggered by "post-nasal drip," sometimes with observable relation of sx to exposure to suspected allergen(s)
    2. Absence of atypical symtoms such as pain, bleeding, fever, purulent discharge, headache, or dyspnea
    3. Physical findings of boggy nasal mucosae often with greyish discoloration
  2. Finding of eosinophils on nasal smear often taken as supporting a diagnosis of allergic rhinitis
  3. Puncture skin tests
    1. A battery of suspected allergens are introduced intradermally by a needle and compared with a positive control (histamine)
    2. Blood tests for specific IgE (e.g. "RAST" and enzyme-linked allergosorbent tests)

II. Management

  1. Avoidance of allergen(s)
    1. Impermeable mattress covers were ineffective at reducing symptoms in a randomized trial of 279 patients with allergic rhinitis (NEJM 349:237, 2003--abst)
  2. Oral antihistamines
    1. First generation--tend to cause somnolence
      1. Diphenhydramine
      2. Chlorpheniramine
  1. Second generation--Don't cross blood-brain barrier as much and cause less somnolence than first-generation
    1. Loratadine (Claritin) 10mg PO QD for age 6y and up; 2-5y, 5mg PO QD--less effective than others
    2. Fexofenadine (Allegra) 60mg BID or 180mg QD (for adults); 30mg BID 6-11yo--less sedating than others
    3. Cetirizine (Zyrtec) 5-10mg QD for age 6y and up; for 2-5y, 2.5-5mg PO QD
    4. Desloratadine (Clarinex)
  1. Nasal Corticosteroids
    1. Typically prescribed on a scheduled, not PRN, basis
    2. Fluticasone intranasal used PRN ass'd with lower sx scores than placebo though didn't compare with daily Fluticasone, in a randomized trial of 56 pts with seasonal allergic rhinitis (J. All. Clin. Immunol. 105:732, 2000--JW)
  2. Comparisons of nasal corticosteroids vs. oral antihistamines
  1. Nasal steroids apparently much better than oral antihistamines for allergic rhinitis in one meta-analysis of 16 randomized trials involving 2,267 pts (BMJ 317:1624, 1999--JW)
  2. 348 pts with allergic rhinitis randomized to 4wks of Seldane 60mg BID vs. fluticasone nasal spray 200ug/d vs. placebo; fluticasone caused sig. better improvement than seldane in nasal obstruction, rhinorrhea, sneezing, and nasal itching. Seldane sig. better than placebo only for sneezing. Sponsored by maker of fluticasone (J. All. Clin. Immunol. 97:915, 1996-JW)
  3. 569 pts > 12yo w/allergic rhinitis randomized to fluticasone propionate nasal spray 2 sprays to each nostril QD vs. loratadine 10mg QD vs. both vs. double-placebo. Fluticasone alone was better than loratadine alone and the two together weren't sig. better than loratadine alone (J. Fam. Prac. 47:118, 1998--JW)
  1. Azelastine HCL (Astelin) 2 sprays each nostril BID
    1. An H-1 antagonist nasal spray
    2. More effective at decreasing sx than Cetirizine PO
    3. As effective as beclomethasone nasal
    4. Side effects include somnolence and bitter taste; shown to be teratogenic in mice and NOT RECC'D DURING PREGNANCY (Med. Letter 39:45, 1997)
  2. Montelukast 10mg PO QD approved in 2003 for use for seasonal allergic rhinitis in pts > 2yo; less effective than intranasal steroids in head-to-head randomized trials (Med. Lett. 45:21, 2003)
  3. In a study in 91 pts with allergic rhinitis randomized to petrolatum vs. placebo (carboxymethylcellulose gel) to nasal mucosae QID x 3d, the petrolatum group had sig. greater sx relief (Arch. Oto. Head Neck Surg. 130:979, 2004--AFP)
  4. Butterbur (Petasites hybridus, aka exwort or bog rhubarb)
    1. Butterbur 8mg (total petasine) QID ass'd with similar degrees of symptom control as Cetirizine 10mg QD in a 2wk randomized trial in 125 pts with seasonal allergic rhinitis (BMJ 324:144, 2002--JW)
  5. Acupuncture
    1. Acupuncture 2x/wk x 8wks was ass'd with sig. greater improvements in mean sx scores than sham acupuncture in a randomized study in 82 pediatric patients (mean age 11.7yo) with allergic rhinitis (Peds. 114:1242, 2004--abst)