Parosmia

Parosmia, from the Greek < para = osmi, also known as troposmia (Gk.) or cacosmia, (Gk.) is an olfactory dysfunction that is characterized by the inability of the brain to properly identify an odor’s “natural” smell. What happens instead, is that the natural odor is transcribed into what is most often described as an unpleasant aroma, typically a “‘burned,’ ‘rotting,’ ‘fecal,’ or ‘chemical’ smell.” There are instances, however, of pleasant odors. This is more specifically called euosmia (Gk.).

Diagnosing

One method used to establish parosmia is the University of Pennsylvania Smell Identification Test, or UPSIT. “Sniffin’ Sticks” are another method that can be used to properly diagnose parosmia. These different techniques can also help deduce whether a specific case of parosmia can be attributed to just one stimulating odor or if there is a group of stimulating odors that will generate the displaced smell. One case study performed by Frasnelli et al. offers a situation where certain smells, specifically coffees, cigarettes, onions, and perfumes, induced a “nauseating” odor for the patient, one which was artificial but unable to be aptly related to another known smell. In another case study cited in the same paper, one woman had parosmia in one nostril but not the other. Medical examinations and MRIs did not reveal any abnormalities; however the parosmia in this case was degenerative and only got worse with time. The authors do comment, however, that cases of parosmia can predict regeneration of olfactory senses.

Parosmia (moth)

Parosmia is a genus of moths of the Noctuidae family.

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