title: The loss of smell in persistent allergic rhinitis is improved by levocetirizine due to reduction of nasal inflammation but not nasal congestion (the CIRANO study).
abstract: BACKGROUND
  Persistent allergic rhinitis (PER) has a moderate impact on the sense of smell, but no controlled study has reported the effect of antihistamines on the loss of smell in patients with PER.
  
  
  METHODS
  Patients with PER and subjective loss of the sense of smell (n = 27) were included in this pilot randomised, double-blind, placebo-controlled study. Nasal symptoms, nasal endoscopy, skin prick test, acoustic rhinometry, peak nasal inspiratory flow, nasal nitric oxide (nNO), and olfactometry (Barcelona Smell Test-24; BAST-24) were performed and evaluated in all PER patients at baseline and after 7 and 30 days of treatment with levocetirizine 5 mg or placebo.
  
  
  RESULTS
  The study population was randomized into two homogeneous groups: levocetirizine (n = 14) and placebo groups (n = 13). The evolution of symptoms reflected the therapeutic effect of levocetirizine treatment on rhinorrhea, nasal itching, eye itching, sneezing, and the total symptoms score after 7 and 30 days. Significant improvement in loss of smell by a visual analog scale (VAS) was observed after 7 days of levocetirizine treatment (7.2 ± 4.3; p < 0.05) compared to placebo (-9.4 ± 6.2). Improvement in smell identification by BAST-24 was strongly correlated (r = 0.72; p < 0.05) with smell improvement by VAS after 30 days. After 7 days of treatment with levocetirizine, the nNO values decreased (-494 ± 188) compared to placebo (155 ± 284 ppb; p < 0.05).
  
  
  CONCLUSIONS
  The CIRANO study suggests that levocetirizine is effective on PER symptoms, including a transient improvement in loss of smell, and that this improvement concurs more with reduction of nasal inflammation than of nasal patency.
authors.affiliation: Rhinology Unit and Smell Clinic, Department of Otorhinolaryngology, Head and Neck Surgery, Hospital Clínic i Universitari de Barcelona, Barcelona, Spain. guilemany@gmail.com
authors.forename: José Maria
authors.initials: JM
authors.lastname: Guilemany
authors.forename: Alfons
authors.initials: A
authors.lastname: García-Piñero
authors.forename: Isam
authors.initials: I
authors.lastname: Alobid
authors.forename: Silvia
authors.initials: S
authors.lastname: Centellas
authors.forename: Franklin Santiago
authors.initials: FS
authors.lastname: Mariño
authors.forename: Antonio
authors.initials: A
authors.lastname: Valero
authors.forename: Manuel
authors.initials: M
authors.lastname: Bernal-Sprekelsen
authors.forename: César
authors.initials: C
authors.lastname: Picado
authors.forename: Joaquim
authors.initials: J
authors.lastname: Mullol
mesh_terms: D000328:Adult; D017332:Cetirizine / Q000494:pharmacology / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D039563:Histamine H1 Antagonists, Non-Sedating / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D000857:Olfaction Disorders / Q000188:drug therapy* / Q000209:etiology; D010919:Placebos; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology; D012903:Smell
chemical_list: D039563:Histamine H1 Antagonists, Non-Sedating; D010919:Placebos; D009569:Nitric Oxide; C472067:levocetirizine; D017332:Cetirizine