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CC BY 4.0 · Int Arch Otorhinolaryngol
DOI: 10.1055/s-0044-1786046
Systematic Review

Treatments for Olfactory Dysfunction in COVID-19: A Systematic Review

Esmaeil Mehraeen 
1   Department of Health Information Technology, Khalkhal University of Medical Sciences, Khalkhal, Iran
,
Soudabeh Yarmohammadi
2   Trauma Research Center, Kashan University of Medical Sciences, Kashan, Iran
,
Pegah Mirzapour
3   Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran
,
Seyed Saeed Tamehri Zadeh
4   Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
,
Soheil Dehghani
5   School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
,
Leila Molaeipour
6   Department of Epidemiology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
,
Ayoob Molla
7   School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
,
Elaheh Karimi
5   School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
,
Faeze Abbaspour
5   School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
,
SeyedAhmad SeyedAlinaghi
3   Iranian Research Center for HIV/AIDS, Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran
› Author Affiliations Funding The authors declare that they did not receive funding from agencies in the public, private, or not-for-profit sectors for the conduction of the present study.
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Abstract

Introduction Olfactory dysfunction (OD) has emerged as a notable symptom among coronavirus disease 2019 (COVID-19) patients, with its prevalence varying among different populations. Recognizing the need to provide therapeutic solutions for these individuals, the present study seeks to comprehensively review the current evidence on potential underlying mechanisms and treatment modalities to manage OD in COVID-19 patients.

Objective To review the recent evidence on treatments for OD in COVID-19. From the beginning of the study until August 2nd, 2023, we conducted a systematic search on four electronic databases, PubMed, Scopus, Embase, and Web of Science, to find relevant publications.

Data Synthesis In the present study, 37 articles were selected for data extraction and included in the final review. The total number of patients was of 3,560 (2,098 female and 1,462 male subjects). The predominant disorders reported were hyposmia, anosmia, and parosmia. In most of the studies, the pre and postintervention assessments were the same, except for one study, in which the pre-intervention assessment of the disorder was through the SST, Sniffin' Sticks Test (SST), and the post-intervention assessment was through the Visual Analog Scale (VAS) and the 22-item Sinonasal Outcome Test (SNOT-22). The findings suggest olfactory training (OT), ivermectin, palmitoylethanolamide, luteolin, and systemic corticosteroids, in combination with topical corticosteroids, are potential therapies for COVID-19 patients with olfactory impairment.

Conclusion Although the review suggested several medications for OD treatment, further research must delve into the specific impact of OT, a non-pharmacological modality, regarding the mitigation of OD. By continuing to investigate and refine these therapeutic approaches, we can better support COVID-19 patients and improve their quality of life while navigating the challenges posed by OD.

Keywords

COVID-19 - SARS-CoV-2 - olfactory dysfunction - anosmia

Ethics Approval and Consent to Participate

Not applicable


Consent to Publication

Not applicable.


Availability of Data and Material

The authors state that all information provided in the present article could be shared.


Authors' Contributions

EM: conception and design of the study, and final approval of the version to be submitted; SS: conception and design of the study, critical review for important intellectual content, and final approval of the version to be submitted; LM: acquisition, analysis, and interpretation of data; SY, PM, SSTZ, SD, AM, EK and FA: drafting of the article.




Publication History

Received: 02 December 2023

Accepted: 06 March 2024

Article published online:
25 May 2024

© 2024. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit (https://creativecommons.org/licenses/by/4.0/)

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