What is parosmia, the covid-19 symptom sending smell haywire?

·2-min read
Parosmia can be one of the symptoms of covid-19.

If you've had covid-19, you may have noticed that you aren't quite smelling things right or, more precisely, that things suddenly smell disgusting. If that's the case, you could be suffering from parosmia, a change in the perception of smells that can be one of the disease's many symptoms.

While covid-19 can lead to considerably more serious symptoms and consequences, there's no denying its effects on the sense of smell of people infected with the virus. First, there was much talk of anosmia, a word that's been everywhere since the pandemic began, and which describes a loss of the sense of smell. And, if you thought this already debilitating symptom was the virus's only effect on smell, think again, because now, the term on everyone's lips is parosmia.

Some also mention phantosmia, describing phantom smells or smell hallucinations, as certain medical professionals describe them, which isn't quite the same as parosmia. While phantosmia is effectively a smell hallucination, appearing in the absence of any odor, parosmia is a disturbance in the sense of smell, occurring when a smell is perceived but processed differently to usual. And often, the smell perceived is bad. In any case, reports from people who have contracted covid-19 tend to support this, evoking odors of metal, cigarette smoke, ammonia or garbage.

For example, imagine sitting down to your favorite meal or to a glass of wine without being able to smell any of the odors and aromas that would usually be so mouthwatering and delicious. Instead, you smell an odor that makes you feel sick. While parosmia only affects a minority of covid-19 patients (around 10% from the look of several studies), reports of similar experiences are multiplying on social media.

Smells of garlic, gas, rust, garbage, cigarette smoke, and even cleaning products, are some of the main perceptions mentioned by people who have developed parosmia.

To deal with this symptom -- which can last several days or several months -- health professionals may recommend smell training.

Christelle Pellissier