Olfactory training
All patients included during this study received OT as a therapy for
their smell loss.11–13 Olfactory training is defined
as conscious sniffing of (usually four) different odours twice a day for
at least 15 seconds each.13 Participants either
received: (i) four multi-molecule substances with a dominant scent of
the odours stated hereafter for the entire study period (rose odour,
phenyl ethyl alcohol; eucalyptus odour, eucalyptol; lemon odour,
citronella; cloves odour, eugenol), (ii) four single molecule substances
for the entire study period (anise odour, anethol; eucalyptus odour,
eucalyptol; lemon odour, citronella; cloves odour, eugenol), or (iii)
twelve multi-molecule substances, which were alternated twice every
eight weeks as a group of four (first phase: phenyl ethyl alcohol,
eucalyptol, citronella, eugenol; second phase: cinnamon, thyme,
chocolate, peach; third phase: coffee, lavender, honey, strawberry).
Previous studies have shown that the effect of OT in olfactory
rehabilitation is consistent within studies that applied different
training protocols.11–13