International consensus statement on allergy and rhinology: Olfaction

Zara M. Patel, Eric H. Holbrook, Justin H. Turner, Nithin Adappa, Mark W. Albers, Aytug Altundag, Simone Appenzeller, Richard M. Costanzo, Ilona Croy, Greg Davis, Puya Dehgani-Mobaraki, Richard L. Doty, Valerie B. Duffy, Bradley J. Goldstein, David A. Gudis, Antje Haehner, Thomas S. Higgins, Claire Hopkins, Caroline Huart, Thomas HummelKawinyarat Jitaroon, Robert C. Kern, Ashoke R. Khanwalkar, Masayoshi Kobayashi, Kenji Kondo, Andrew P. Lane, Matthias Lechner, Donald A. Leopold, Joshua M. Levy, Michael J. Marmura, Lisha McLelland, Paul J. Moberg, Cristian A. Mueller, Sagar U. Nigwekar, Erin O’Brien, Robert Pellegrino, Carl Philpott, Jayant M. Pinto, Evan R. Reiter, David R. Roalf, Nicholas R. Rowan, Rodney J. Schlosser, James Schwob, Allen M. Seiden, Timothy L. Smith, Zachary M. Soler, Leigh Sowerby, Miwa Takaki, Bruce K. Tan, Andrew Thamboo, Bozena Wrobel, Carol H. Yan

Research output: Contribution to journalArticlepeer-review

55 Citations (Scopus)
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Background: The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O).

Methods: Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus.

Results: The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies.

Conclusion: This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.
Original languageEnglish
Pages (from-to)327-680
Number of pages354
JournalInternational Forum of Allergy & Rhinology
Issue number4
Early online date3 Apr 2022
Publication statusPublished - Apr 2022


  • anosmia
  • evidence-based medicine
  • hyposmia
  • loss of smell
  • olfaction
  • olfactory dysfunction
  • olfactory loss
  • parosmia
  • phantosmia
  • systematic review

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