Using essential oils in rehabilitation of olfactory disorders in patients who have had a new coronavirus infection

Background. SARS-CoV-2 infection often results in olfactory disorder at different levels of the nervous system, which may persist as anosmia, parosmia, hyperosmia, hyposmia, cacosmia, and olfactory hallucinations after recovery.
The aim. To study the effect of essential oils on the restoration of the olfactory apparatus in patients with coronavirus.
Materials and methods. We examined 138 people (mean age 19.9 ± 7.05 years) with olfactory complaints, 60 of them underwent olfactory training with essential oils (EO) for 2 months. Olfactory function was assessed using the Hansen – Roseburg method before and after the training.
Results. After 3 months of using essential oil sets for olfactory training, 27 respondents noted an improvement in the quality of odours and the appearance of previously missing odours. When conducting the Hansen – Roseburg test, a statistically significant improvement in the indicators for determining the tested odorants was revealed: phenylethyl alcohol (PA) – 7 [5; 7]; benzyl acetate (BA) – 6 [4; 6]; formic acid (FA) – 6 [2; 7] (p < 0.05). When repeating the test in the control group of 30 people, only 4 respondents reported an olfaction improvement; the results of the olfactory assessment according to Hansen – Roseburg were as follows: PA – 5 [2; 6], BA – 4 [3; 5], FA – 2 [2; 4] (p > 0.05).
Conclusion. The data obtained after 3 months of olfactory training with a special set of essential oils and the subsequent olfactory testing indicate that olfactory training is a promising method for olfactory restoration, which can help many people regain the joy of perceiving odours and significantly improve their quality of life. The success of the method depends on the correct use of essential oils and compliance with the frequency of training.

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