Effect of Lavender (Lavandula angustifolia L.) syrup on olfactory dysfunction in COVID-19 infection: A pilot controlled clinical trial

Document Type : Short communication


1 Research Institute for Islamic and Complementary Medicine, School of Persian Medicine, Iran University of Medical Sciences, Tehran, Iran

2 Infectious Diseases Research Center, Golestan University of Medical Sciences, Gorgan, Iran

3 Researcher of Persian Medicine, Tehran, Iran

4 Traditional and Complementary Medicine Research Center, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran

5 Ischemic research Center, Golestan University of Medical Sciences, Gorgan, Iran

6 Clinical Research Development Unit (CRDU), Sayad Shirazi Hospital, Golestan University of Medical Sciences, Gorgan, Iran


Objective: The effect of lavender syrup on COVID-19-induced olfactory dysfunction (OD) has been assessed in this study.
Materials and Methods: This pilot clinical trial was conducted in Gonbad-E-Kavoos (Golestan province, Iran). Twenty-three outpatients with COVID-19 and OD in lavender group took 9 ml of lavender syrup/bid for 3 weeks along with the standard COVID-19 treatments and 20 patients in control group took only standard COVID-19 treatments. The severity of OD was assessed by the visual analogue scale (VAS). Data analysis was performed by Friedman and Mann-Whitney tests using SPSS software.
Results: The mean± standard deviation of age was 36.6±9.1, and 42.6±10.4 years (p=0.05), and the duration of symptoms was 7.4±3.5, and 7.5±3.4 days (p=0.98) in the lavender and control group, respectively. The VAS score for OD decreased from 6.8±3.04 to 0.26±0.86 in the lavender group and from 5.3±3.4 to 1±2.61 in the control group. Although, VAS for OD was significantly decreased in both groups (p<0.001), the amount of VAS decrease was 6.6±2.9 scores in the lavender group, and 4.3±4 in the control group (p=0.03). No side effects were observed in the lavender group.
Conclusion: The present study showed that lavender syrup is an effective treatment for COVID-19-induced OD. It is suggested to conduct further studies with larger sample size.