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.


Acikalin A, Gulen M, Kara B, Icme F, Cagliyan
CE, Satar S. 2012. Anticholinergic
syndrome and supraventricular tachycardia
caused by lavender tea toxicity. Keio J
Med, 61: 66.
Aghili Khorasani MH. 2012. Makhzan-alAdvieh. P:140, Tehran, Sabz Arang.
Amin Gh, Bozorgi M, Salari H, Khalaj A,
Zolphaghari B, Rahimi R. 2019.
Ostokhodus. Trad Med Islam & Iran, 10:
Basch E, Foppa I, Liebowitz R, Nelson J, Smith
Lavender and COVID-19-induced anosmia
AJP, Vol. 12, No. 1, Jan-Feb 2022 7
M, Sollars D. 2004. Lavender (Lavandula
angustifolia Miller). J herb pharmacother,
4: 63-78.
Boesveldt S, Postma EM, Boak D, WelgeLuessen A, Schöpf V, Mainland JD. 2017.
Anosmia-a clinical review. Chem senses,
42: 513-523.
Borsetto D, Hopkins C, Philips V, Obholzer R,
Tirelli G, Polesel J. 2020. Self-reported
alteration of sense of smell or taste in
patients with COVID-19: a systematic
review and meta-analysis on 3563 patients.
Rhinol, 58: 430-436.
Brann D, Tsukahara T, Weinreb C, Logan DW,
Datta SR. 2020. Non-neuronal expression
of SARS-CoV-2 entry genes in the olfaory
system suggests mechanisms underlying
COVID-19-associated anosmia. Sci Adv,
6: eabc5801.
Cavanagh HMA, Wilkinson JM. 2002.
Biological activities of Lavender essential
oil. Phytother Res, 16: 301-308.
DA Silva G, Luft C, Lunardelli A, Amaral RH.
2015. Antioxidant, analgesic and antiinflammatory effects of lavender essential
oil. Ann Braz Acad Sci, 87: 1397-1408.
DA Silva JK, Baia Figueiredo PL, Byler KG,
Setzer W. 2020. Essential oils as antiviral
agents, potential of essential oils to treat
SARS-CoV-2 infection: An in-silico
investigation. Int J Mol Sci, 21: 3426.
Doulaptsi M, Prokopakis E, Seys S, Pugin B,
Steelant B, Hellings P. 2018. Visual
analogue scale for sino-nasal symptoms
severity correlates with sino-nasal outcome
test 22: paving the way for a simple
outcome tool of CRS burden. Clin Transl
Allergy, 8: 32.
Fleming T. 2009. PDR for herbal medicines. p:
529, USA, Thomson health care Inc.
Gengler I, Wang JC, Speth MM, Sedaghat AR.
2020. Sinonasal pathophysiology of SARSCoV-2 and COVID-19: A systematic
review of the current evidence.
Laryngoscope Investig Otolaryngol, 5:
Goncalves S, Goldstein BJ. 2016.
Pathophysiology of olfactory disorders and
potential treatment strategies. Curr
otorhinolaryngol rep, 4: 115-121.
Hajhashemia V, Ghannadi A, Sharif B. 2003.
Anti-inflammatory and analgesic
properties of the leaf extracts and essential
oil of Lavandula angustifolia Mill. J
Ethnopharmacol, 89: 67-71.
Han AY, Mukdad L, Long JL, Lopez IA. 2020.
Anosmia in COVID-19: mechanisms and
significance. Chem senses, 45: 423-428.
Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y.
2020. Clinical features of patients infected
with 2019 novel coronavirus in Wuhan,
China. Lancet, 395: 497-506.
Klopfenstein T, Kadiane-Oussou NJ, Toko L,
Royer PY, Lepiller Q, Gendrin V. 2020.
Features of anosmia in COVID-19. Med
mal infect, 50: 436-439.
Koulivand PH, Khaleghi Ghadiri M, Gorji A.
2013. Lavender and the Nervous System.
Evid-Based Complement Altern Med,
2013: 681304.
Laurendon T, Radulesco T, Mugnier J, Gérault
M, Chagnaud C, El Ahmadi A-A. 2020.
Bilateral transient olfactory bulb edema
during COVID-19–related anosmia.
Neurol, 95: 224-225.
National committee of management of COVID19, Ministry of health of Islamic republic of
Iran. The flowchart of diagnosis and
treatment of COVID-19 in outpatient and
inpatient services. Available at
[https://iums.ac.ir/content/98416, April
Nileeka Balasuriya BW, Vasantha Rupasinghe
HP. 2011. Plant flavonoids as angiotensin
converting enzyme inhibitors in regulation
of hypertension. Funct Food Health Dis, 5:
Spinato G, Fabbris C, Polesel J, Cazzador D,
Borsetto D, Hopkins C. 2020. Alterations in
smell or taste in mildly symptomatic
outpatients with SARS-CoV-2 infection.
JAMA, 323: 2089-2091.
Sungnak W, Huang N, Bécavin C, Berg M,
Queen R, Litvinukova M. 2020. SARSCoV-2 entry factors are highly expressed in
nasal epithelial cells together with innate
immune genes. Nat med, 26: 681-687.
Vimalanathan, S, Hudson J. 2014. Antiinfluenza virus activity of essential oils and
vapors. Am J Essent Oils Nat Prod, 2: 47-
Whitcroft KL, Hummel T. 2020. Olfactory
dysfunction in COVID-19: Diagnosis and
management. JAMA, 323: 2512-2514.