The scents of so many things can bring joy. For some people, it may be the aroma of fresh-cut grass or blooming flowers. For others, the scent of bread baking can bring feelings of calm and serenity. Smells can also warn of danger, letting us know there’s a fire, or food has gone bad. The inability to smell can greatly impact the quality of life. This is medically called Parosmia.
Some people may experience parosmia after having COVID-19. Parosmia is a smell disorder where odours become distorted. In this explainer, we cover what we know so far about parosmia after COVID-19, including potential causes, duration, and treatment.
What is parosmia?
“Parosmia can be caused by a number of things such as respiratory infections, seizures, and even brain tumours,” says Richard Orlandi, MD, an ear, nose, and throat physician and professor in the Department of Surgery at the University of Utah Health.
Orlandi said Parosmia “seem to be on the rise since the pandemic” as more COVID-19 recovered patients now report this symptom.
“Your sense of smell is important,” Orlandi says. “It’s what helps you enjoy food and sense danger, as in the case of smoke. It’s connected to our memories, such as the way your mom or grandma’s perfume smells. Depending on the severity, this condition can range from an annoyance to a frustrating and anxiety-inducing symptom,” he added.
With parosmia, “a person may be looking at a rose but it smells like a burned piece of paper,” says Brent A. Senior, MD, professor of otolaryngology/neurosurgery at the University of North Carolina at Chapel Hill.
What causes parosmia?
Parosmia can have a variety of causes, including upper respiratory tract infections, head injuries, sinus problems, exposure to toxins.
How parosmia can affect the quality of life
Experiencing parosmia can have a big impact on quality of life. For example, people with parosmia may also have reduced appetite, weight loss, depression etc.
Medical experts say Parosmia can also affect a person’s life in other ways. For example, some jobs may be hard to do, particularly if scents are important. Examples of occupations that may be affected include chefs, florists, and firefighters.
There’s also an increased risk of not noticing hazards at home, like not being able to smell burning food, smoke, or gas.
What is the relationship between parosmia and COVID-19?
Some people experience parosmia after having COVID-19. In fact, changes in smell or taste like parosmia are one of the many potential symptoms of long-haul COVID-19.
Some types of distorted odours people with parosmia report include sewage or garbage, rotten meat or eggs, smoky or burnt, gasoline, metallic, ammonia or vinegar, mouldy socks, skunk.
Who’s at risk for getting parosmia after COVID-19?
If loss of smell and taste was one of your acute COVID-19 symptoms, you may be at increased risk of parosmia. In many cases, people with parosmia also experienced a loss of smell and taste while they were sick with COVID-19.
How common is parosmia after COVID-19?
Researchers are still racing to determine how common parosmia after COVID-19 actually is. One June 2021 surveyTrusted Source found that out of the 1,299 survey respondents, 140 of them (10.8 per cent) reported having parosmia after COVID-19.
The same study found that half of these people reported a sudden onset of parosmia, while the other half reported a gradual onset.
Based on current infection estimates, there could be 7 million people worldwide with parosmia as a result of Covid-19, the researchers calculated.
“This is on a scale that we’ve never seen before,” says Dr Duika Burges Watson at Newcastle University, who has been studying the psychological impact of parosmia.
How long does parosmia after COVID-19 last?
Generally speaking, parosmia after COVID-19 can gradually fade with time. However, it may take weeks or months to see an improvement.
A May 2021 study trusted Source found that participants reported parosmia that lasted anywhere between 9 days and 6 months. The average duration of parosmia was 3.4 months.
Is there anything you can do to treat parosmia?
Parosmia due to COVID-19 often resolves on its own over time. But you may be wondering what else you can do as you recover.
“The treatment for loss of smell depends on the cause. There are medical interventions which can help, as well as at-home treatments,” says Nicole Dr Aaronson, is a Professor of Otolaryngology and Pediatrics at Thomas Jefferson Sidney Kimmel School of Medicine.
A technique called smell training may be used to treat parosmia due to COVID-19. You may also see this referred to as olfactory training. Medical experts say Smell training involves sniffing the same group of scents for 20 over a time. This is typically done at least twice per day for 3 months or longer.
Making various lifestyle changes may also help as you recover from parosmia. These typically involve avoiding certain scents that may trigger it. For example:
Limit preparation or consumption of certain foods that commonly trigger parosmias, such as meats, onions, or eggs.
Focus on blander food items, such as oatmeal or steamed vegetables, which may be less likely to trigger parosmia.
Eat foods that are cold or at room temperature, as heat can enhance scents.
Aim to avoid areas that are associated with strong scents, such as the grocery store, restaurants, or the perfume counter at a department store.
Open the windows or use a fan to help dissipate scents that trigger parosmia.
This story is supported by Journalists for Human Rights under the Mobilizing Media to Fighting Covid-19 project.