Parosmia is defined as having an impaired sense of smell. The person may suddenly realize that something smells bad. The olfactory cells are called olfactory sensory neurons located in the nose. Parosmia occurs when these neurons do not detect odors and do not transmit them to the brain. For example, if you smell a perfume that smells good, it may smell bad to your nose. Parosmia is a common condition after a viral infection.
The senses play a big role in everyday life. Good smells can generally lift a person's mood and bring happiness. On the other hand, an impaired sense of smell can have a major impact on quality of life. It can lead to the following problems
- Loss of appetite
- Weight loss
- Depression
When the sense of smell is impaired, it can be assumed that almost all food is spoiled. If you work in professions where the sense of smell is important, such as cooking, perfumery and firefighting, parosmia can make these work areas difficult.
What Causes Parosmia?
Sometimes the only symptom of getting coronavirus can be an olfactory disorder. In studies, olfactory impairment was observed in 70 percent of people infected with coronavirus. Some conditions can lead to parosmia. We can list these conditions as follows;
- Upper respiratory tract infections such as colds
- Head injury
- sinus infections
- Some toxins and medicines
- Seizures in the part of the brain called the temporal lobe
- Brain tumor
- COVID-19
- Persistent dry mouth
COVID-19 and Parosmia
Total loss of smell and taste are the hallmark symptoms of COVID-19. According to studies, the coronavirus that causes COVID-19 has been reported to have happened to at least 25% of people who contracted SARS-CoV-2. Some reports have also linked COVID-19 infections to parosmia.
Most people who completely lose their sense of smell (anosmia) due to COVID-19 find that their senses return to normal over time. But problems can linger in a few people, or they may have changes in their sense of taste and smell weeks or months after infection.
About half of people with COVID-19 who participated in one study reported having parosmia about 2.5 months after their first infection, and it persisted for at least 6 months.
Another international study observed that 7% of people reported an impaired sense of smell after COVID-19 infection. However, experts say more information and larger studies are needed to better understand how the disease can affect smell and taste.
Parosmia Diagnosis and Treatment
If parosmia is suspected, a specialist should be consulted. There is no standardized test for this condition. The specialist will also do a physical examination and ask about your medical history to check for serious underlying problems such as brain tumors.
They may try to rule out a similar condition called phantosmia. Unlike parosmia, where your nose can still smell things, phantosmia is when your olfactory receptors hallucinate and detect odors that are not there. Phantosmia is not constant; it can come and go. Your doctor may refer you to a different specialist to rule out nerve damage or head injuries;
- otolaryngologists specializing in ear, nose and throat conditions
- Neurologists who focus on conditions related to thebrain and nervous system
- Allergists dealing with allergies and related problems
Your doctor may prescribe medication to treat parosmia. Studies have shown that these medicines can relieve symptoms. If medicines don't work, you may have surgery to remove the damaged sensory receptors (olfactory mucosa) in your nasal cavity. However, doctors only recommend surgery if it is necessary, as it is a complex procedure with high risks.
There is no cure for parosmia caused by a viral infection such as COVID-19 or a head injury. Damaged nerves in your nose and nasal cavity can regrow, so without treatment your sense of smell may partially or fully return.