[1] Instead, the natural odor is usually transformed into an unpleasant aroma, typically a "burned", "rotting", "fecal", or "chemical" smell.
In a case study, Frasnelli et al. examined five patients that endured parosmia or phantosmia, most as a result of upper respiratory tract infections (URTIs).
[6] Common triggers in COVID-19 related parosmia include coffee, chocolate, meat, onion, and toothpaste.
[citation needed] Different types of head trauma could also lead to dysfunctions that relate to what the afflicted brain area controls.
Although the specific pathway is undetermined, the lack of dopamine has resulted in documented cases of parosmia and phantosmia.
Medical examination including MRI did not reveal any abnormalities; however the parosmia in this case was degenerative, getting worse in time.