J Rhinol.  2022 Nov;29(3):127-133. 10.18787/jr.2022.00407.

Practical Review of Olfactory Training and COVID-19

• Hwang SH
• Kim JS
• Choi BY
• Kim JK
• Kim BG

• KMID: 2536580
• DOI: http://doi.org/10.18787/jr.2022.00407

Abstract

Olfactory disorders one of the most frequent distinctive symptoms of COVID-19 infection. COVID-19-induced olfactory disorder can be classified as post-infectious olfactory dysfunction (PIOD). The effect of drugs on olfactory disorder following upper respiratory infection, including PIOD, has not been clearly established, which adds to the difficulty with treating the disorder. However, the effect of olfactory training on PIOD has been confirmed by numerous studies. As such, olfactory training is gaining attention, and has taken on greater importance, as the sole treatment for COVID-19–induced olfactory disorder in this pandemic age. This review describes the effect of olfactory training for COVID-19–induced olfactory disorder by analyzing the relevant literature.

Keyword

COVID-19; Olfactory impairment; Olfactory training; Upper respiratory infections

Figure

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  Fig. 1. Diagram of selection of studies.

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  Fig. 2. Post-treatment (olfactory training) versus pre-treatment with SMD. SMD of olfactory score (total: number of participants per group). SD, standard deviation; SMD, standard mean difference; CI, confidence interval.

• 

  Fig. 3. Post-treatment (olfactory training) versus pre-treatment with OR. Percentage of olfactory dysfunction (total: number of participants per group). OR, odds ratio; CI, confidence interval.

Reference

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