International Journal of Medical and All Body Health Research  |  e-ISSN: 2582-8940  |  Double-Blind Peer Review  |  Open Access  |  CC BY-NC-SA 4.0

Current Issues
     2026:7/4

International Journal of Medical and All Body Health Research

e-ISSN: 2582-8940 | Open Access

Post-COVID-19 Olfactory Disorders: Diagnosis, Prognosis, and Treatment Strategies

Cecília Marques Meirelles, José A N Neto, Jonhata N da Conceição, Ana Paula Valente Pinho Mafetano, Maria Luiza Cunha Barbosa, Ana Nogueira Ervilha, Ana Luiza Trindade Bellucci, Giovana Casarini Yamashiro, Leonardo Alexandre Ponsoni, Bruna Lima Pellicciotti, Maria Carolinne Feitosa de Lyra Amorim Ferreira, Amanda Pinheiro Serpa, Marco Aurélio S Couto, Délio Tiago M Malachias, Filipe J L Garcia, Roselene de O Carvalho, Regilane da S Batista, Wellington da Silva P da Cunha, Carlos Henrique B Figueiredo de Mendonça, Rubens R Tutela, Laura Carvalho Ishi, Vitória Faria Corradi, Giulia Cândido Campos Marcondes, Enzo Maruzzo, Thais Silva Picolli, Lucas Pereira Sales Porto, Thiago Augusto Rochetti Bezerra, Joel Eloi Belo Junior

Central University of Paraguay, School of Medicine, Paraguay; Metropolitan University of Santos (UNIMES), Santos, São Paulo, Brazil; FACERES University Center, São José do Rio Preto, São Paulo, Brazil; Nove de Julho University (UNINOVE), São Bernardo do Campo Campus, São Bernardo do Campo, São Paulo, Brazil; University of Ribeirão Preto (UNAERP), Guarujá, São Paulo, Brazil; University of Taubaté (UNITAU), Taubaté São Paulo, Brazil; São José dos Campos School of Medical Sciences, São José dos Campos, São Paulo, Brazil; Médico, Federal University of Roraima (UFRR), Boa Vista, Roraima, Brazil; São Judas Tadeu University, Cubatão, São Paulo, Brazil; The Pennsylvania State University, Pennsylvania, United States of America; Ribeirão Preto School of Medicine, University of São Paulo (FMRP-USP), Ribeirão Preto, São Paulo, Brazil

Article Information

Volume / Issue7 / 2 (April-June 2026)
Pages251-260
AccessOpen Access

Publication Timeline

  • Received05 April 2026
  • Accepted04 May 2026
  • Published

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Abstract

Introduction: Olfactory changes associated with COVID-19 have emerged as one of the most common neurosensory manifestations of SARS-CoV-2 infection. Although many patients experience spontaneous recovery, a significant proportion develops persistent olfactory dysfunction, impacting quality of life, nutrition, environmental safety, and mental health. Objective: To analyze the most recent scientific evidence regarding diagnosis, prognosis, and therapeutic strategies related to post-COVID-19 olfactory changes. 
Methods: A systematic literature review was conducted following the PRISMA 2020 guidelines. Searches were performed in the PubMed/MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library databases, including studies published between January 2021 and June 2026. After applying eligibility criteria and removing duplicates, 60 studies were selected for qualitative synthesis. 
Results: The studies demonstrated that the pathophysiology of post-COVID olfactory dysfunction involves inflammatory changes in the olfactory epithelium and possible central impairments of olfactory-related neural pathways. Objective diagnostic methods, such as UPSIT and Sniffin’ Sticks, proved essential for the proper assessment of olfactory function. Among the prognostic factors associated with symptom persistence, advanced age, greater initial severity of olfactory loss, and the presence of parosmia stood out. Olfactory training presented the highest level of scientific evidence and is considered the primary therapeutic strategy. Pharmacological therapies and emerging approaches, such as palmitoylethanolamide combined with luteolin and platelet-rich plasma, have shown promising results but still require further validation. 
Conclusion: Post-COVID-19 olfactory changes remain a significant clinical challenge, requiring early diagnosis, multidisciplinary follow-up, and therapeutic strategies grounded in scientific evidence.
 

Keywords

COVID-19Olfactory DysfunctionAnosmiaPrognosisOlfactory Training

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How to Cite

Meirelles, C. M., Neto, J. A. N., Conceição, J. N. D., Mafetano, A. P. V. P., Barbosa, M. L. C., Ervilha, A. N., Bellucci, A. L. T., Yamashiro, G. C., Ponsoni, L. A., Pellicciotti, B. L., Ferreira, M. C. F. D. L. A., Serpa, A. P., Couto, M. A. S., Malachias, D. T. M., Garcia, F. J. L., Carvalho, R. D. O., Batista, R. D. S., Cunha, W. D. S. P. D., Mendonça, C. H. B. F. D., Tutela, R. R., Ishi, L. C., Corradi, V. F., Marcondes, G. C. C., Maruzzo, E., Picolli, T. S., Porto, L. P. S., Bezerra, T. A. R., & Junior, J. E. B. (2026). Post-COVID-19 Olfactory Disorders: Diagnosis, Prognosis, and Treatment Strategies. International Journal of Medical and All Body Health Research, 7(2), 251-260. https://doi.org/10.54660/IJMBHR.2026.7.2.251-260

Meirelles, Cecília Marques, et al. "Post-COVID-19 Olfactory Disorders: Diagnosis, Prognosis, and Treatment Strategies." International Journal of Medical and All Body Health Research, vol. 7, no. 2, 2026, pp. 251-260. https://doi.org/10.54660/IJMBHR.2026.7.2.251-260.

Meirelles, C. M., Neto, J. A. N., Conceição, J. N. D., Mafetano, A. P. V. P., Barbosa, M. L. C., Ervilha, A. N., Bellucci, A. L. T., Yamashiro, G. C., Ponsoni, L. A., Pellicciotti, B. L., Ferreira, M. C. F. D. L. A., Serpa, A. P., Couto, M. A. S., Malachias, D. T. M., Garcia, F. J. L., Carvalho, R. D. O., Batista, R. D. S., Cunha, W. D. S. P. D., Mendonça, C. H. B. F. D., Tutela, R. R., Ishi, L. C., Corradi, V. F., Marcondes, G. C. C., Maruzzo, E., Picolli, T. S., Porto, L. P. S., Bezerra, T. A. R. and Junior, J. E. B. (2026) 'Post-COVID-19 Olfactory Disorders: Diagnosis, Prognosis, and Treatment Strategies', International Journal of Medical and All Body Health Research, 7(2), pp. 251-260. doi: 10.54660/IJMBHR.2026.7.2.251-260.

Meirelles CM, Neto JAN, Conceição JND, Mafetano APVP, Barbosa MLC, Ervilha AN, et al. Post-COVID-19 Olfactory Disorders: Diagnosis, Prognosis, and Treatment Strategies. International Journal of Medical and All Body Health Research. 2026;7(2):251-260. doi:10.54660/IJMBHR.2026.7.2.251-260

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