Parosmia is a term that refers to the disruption of the normal sense of smell. This can manifest as a distortion of the normal sense of smell, in which everyday foods or objects take on a strong and disagreeable odor, or the loss of ability to recognize or detect certain scents. The symptoms of parosmia may be worse around foods, leading to nausea, loss of appetite, and weight loss if the condition persists. The severity of parosmia may vary among affected people.
Parosmia is usually caused by damage to the olfactory sensory neurons that are found in the nose. The condition has been reported as a complication of SARS-CoV-2 (COVID-19) infection and can also result from bacterial and viral infections that involve the upper respiratory tract, including colds, flu, and sinus infections. Damage to the parts of the brain that process smell sensations through trauma or stroke can also cause parosmia. Toxins, chemicals, neurologic conditions, radiation exposure, cigarette smoking, and certain medications are other possible causes of parosmia.