An interventional study of Olfactory Training and Control in Olfaction Disorders, Smell Disorders and Anosmia, sponsored by Pamela Youde Nethersole Eastern Hospital. Recruiting at 1 site in Hong Kong. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-06-03.
Sponsored by Pamela Youde Nethersole Eastern Hospital · Not applicable, Interventional, and Treatment
Design Prospective double-blinded randomized control trial.
Study Period 1/7/2022 - 30/6/2024 for case recruitment.
Suitable patient will be recruited. Informed consent will be signed. Objective smell assessment will be done using the University of Pennsylvania Smell Identification Test (UPSIT) and Butanol Threshold Test (BTT). Subjective quality of life score will be obtained by Sino-Nasal Outcome Test (SNOT-22). Subjective smell and taste assessment will be assessed by Visual Analogue Scale (VAS). Patient will be randomized into treatment group and control group using computer generated list by an independent nursing staff. Doctors and the patients will be blinded during the study.
180 studies on the registry are indexed under Anosmia; 45 are open to participants now.
This study's planned enrollment of 80 is above the median of 60 across 114 interventional studies indexed under Anosmia.
Browse Anosmia studies →Pamela Youde Nethersole Eastern Hospital is the lead sponsor of 12 studies on the registry; 3 are open to participants now.
Compared within Anosmia, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Olfaction Disorders. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Olfactory training by neurological chemosensory stimulation using aromatic substances delivered via diffusers. Four aromatic substances will be used. Each substance will be given for 20 seconds sequentially, providing a total of 80 seconds of olfactory stimulation three times per day for 3 months.
Other: Olfactory Training
Same diffuser will be given to control group. All of the four essential oils will be replaced by normal saline using the same packing. Same treatment regime of 20 seconds for each diffuser three times per day for 3 months will be instructed to control group patients.
Other: Control
Four aromatic substances will be used (Citrus limon, Eucalyptus radiata, Pelargonium graveolens, Juniperus virginiana)
Normal Saline will be used
Olfactory threshold changes after olfactory training after 3 months
Parameter: Olfactory threshold using Butanol Threshold Test (BTT)
Time frame: 3 months after starting smell training
Olfactory identification score changes after olfactory training after 3 months
Parameter: Olfactory identification using Smell Identification Test (UPSIT)
Time frame: 3 months after starting smell training
Quality of life changes after olfactory training after 3 months
Parameter: Subjective quality of life score using Sino-Nasal Outcome Test (SNOT-22)
Time frame: 3 months after starting smell training
Taste and smell changes after olfactory training after 3 months
Parameter: Subjective smell and taste assessment using Visual Analogue Scale (VAS)
Time frame: 3 months after starting smell training
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2022 (actual). Primary completion is estimated for Jun 2027, 59 months after the start.
Of 50 non-industry interventional studies with no phase under Anosmia, half reached primary completion within 28 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 37. This study's planned 59 months is above that.
Counting every sponsor, half of 50 studies reached it within 28 months; a quarter within 14 and three quarters within 37.
How these figures are worked out, and which studies are left out of them.
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Pamela Youde Nethersole Eastern Hospital