Aim: The aim is to investigate the effect of olfactory training with essential oilsversus olfactory training with placebo-oils in patients with COVID-19 induced olfactorydysfunctionStudy design: The study is a placebo-controlled randomized clinical trial with anintervention group and a control group. The intervention group receive four essentialoils with scents of orange, lavender, clove, and peppermint. Patients in the controlgroup receive a fragrance kit, consisting of the same containers, but with fragrance-freeoils added. Both groups are instructed to smell each of the four oils for 30 seconds inthe morning and evening, over a three-month intervention period. Patients are given adiary in which to record their olfactory training. The nurse or medical studentinstructing the patients in the training and performing the smell and taste tests isblinded.Study population: Patients referred to the Unit for Sense of Taste and Smell in theDepartment of Otorhinolaryngology Head & Neck and Audiology at Rigshospitalet.Inclusion criteria: - Impaired sense of taste and smell following COVID-19 > 3 months - Hyposmia (16.25-30.5) or anosmia (
Not Provided
Other: Olfactory training with essential oils
Olfactory training twice daily with essential oils from Urtegaarden Aps with scents of
orange, lavender, clove and peppermint. The olfactory training is performed every morning
and evening, by smelling each of the oils for 30 seconds.
Other Name: Urtegaarden ApS Essential Oils
Other: Olfactory training with fragrance-free oils
Olfactory training twice daily with fragrance-free oils from Urtegaarden Aps in the same
four containers as the intervention group. The olfactory training is performed every
morning and evening, by smelling each of the oils for 30 seconds.
Other Name: Urtegaarden ApS Essential Oils (Fragrance-free custom made)
Inclusion Criteria:
- Olfactory dysfunction caused by COVID-19
- Hyposmia (16.25-30.5) or anosmia (<16) with or without parosmia assessed by TDI test
with Sniffin Sticks performed in the Unit for Sense of Taste and Smell
- > 18 years of age
Exclusion Criteria:
- Cause of hyposmia, anosmia or parosmia other than COVID-19
- Does not read or speak Danish
- Lack of compliance to perform daily olfactory training
Department of Otorhinolaryngology, Head and Neck Surgery & Audiology, Copenhagen University Hospital
Copenhagen, Denmark
Investigator: Ditte Gertz Mogensen, PhD-student
Contact: +45 35457508
ditte.gertz.mogensen@regionh.dk
Ditte G Gertz Mogensen, PhD-student
+45 35457508
ditte.gertz.mogensen@regionh.dk
Vibeke Backer, Professor
+45 35456033
nina.vibeke.backer@regionh.dk
Vibeke G Backer, Professor, Study Chair
Rigshospitalet, Denmark