Parosmia is a distorted sense of smell. It happens when smell receptor cells in your nose don’t detect odors or transmit them to your brain. Causes include bacterial or viral infections, head trauma, neurological conditions and COVID-19. Parosmia is usually temporary, but in some cases, it’s permanent.
Parosmia is a condition that distorts your sense of smell. People with parosmia may be unable to experience the full range of scents in their environment. Or the odors they detect smell “wrong.” For instance, warm cookies from the oven — which smell sweet and delicious to most people — might smell unpleasant and rotten to people with parosmia.
You may hear people refer to this condition as anosmia. But anosmia refers to a total loss of sense of smell. Anosmia and parosmia are both common symptoms of COVID-19, along with dysgeusia (a distorted sense of taste) and ageusia (a total loss of sense of taste).
Parosmia is a common condition, even more prevalent since the onset of COVID-19. In 2007, one study found that approximately 3.9% of adults experience parosmia at some point. A 2021 study — published over a year after the first COVID-19 case appeared in the U.S. — estimated that 40% to 75% of people with COVID-19 develop parosmia.
In addition, the average onset for parosmia in people with COVID-19 is three months after the initial infection. Parosmia is a common long COVID symptom.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Parosmia symptoms vary from person to person. Some cases are mild and short-lived. Others are severe and long lasting. In most cases, people start to notice parosmia symptoms after recovering from an infection.
People with parosmia might:
There are several different conditions that can cause parosmia, including:
While parosmia itself isn’t spreadable, the infections that cause it are contagious. To reduce your risk, be sure to distance yourself from anyone who’s sick and practice good hygiene habits.
A healthcare provider, usually an otolaryngologist (ENT), will ask about your health history, including recent infections, current medications and lifestyle factors (such as smoking). Next, they’ll likely ask you to sniff different substances, and then describe the scent.
In some cases, your healthcare provider may request additional tests, including:
These tests can help your provider determine the underlying cause of parosmia so they can recommend appropriate care.
Parosmia treatment depends on the cause. While the vast majority of people eventually regain a partial or full sense of smell, a small number of people never do.
If parosmia is the result of environmental factors — like smoking, medications or chemical exposure — your sense of smell will likely return once you remove those triggers. Be sure to consult your healthcare provider before stopping any medications.
In some cases, your provider may prescribe medication to ease parosmia symptoms. Research is ongoing, but studies suggest that these drugs may help restore your sense of smell:
Also called “smell training,” this approach involves sniffing various substances for several seconds at a time. You repeat the process twice a day for several months. Your healthcare provider can let you know if this is an option for you.
If parosmia is a symptom of nasal polyps or a brain tumor, then your healthcare provider may recommend surgery.
Sometimes, a surgeon can remove the damaged sensory receptors in your nose to restore your sense of smell. But this is a complex procedure and the risks often outweigh the benefits. Explore your options thoroughly before deciding on treatment.
Because parosmia is often the result of trauma, viruses and other uncontrollable factors, it’s not possible to prevent it completely. But if parosmia is due to environmental factors, like smoking or chemical exposure, removing those triggers should reduce or eliminate your symptoms.
To reduce your risk of bacterial- and viral-related parosmia, wash your hands frequently and follow all U.S. Centers for Disease Control and Prevention (CDC) recommendations and guidelines.
Parosmia is one of the most common long COVID symptoms. According to one research study, people with COVID-related parosmia start to regain their sense of smell approximately 14 to 16 months after infection.
Yes. In some cases, parosmia is permanent. But full recovery is common. Ask your healthcare provider for details about your situation.
Current research suggests that COVID-related parosmia is only temporary, though symptoms can last for a year or longer.
Anytime you notice a distorted or absent sense of smell, you should schedule an appointment with a healthcare provider. They can determine why you have parosmia and whether you need treatment for an underlying condition.
A note from Cleveland Clinic
Parosmia is a distorted sense of smell. Things that used to smell pleasant now smell foul to people with parosmia. People get parosmia for many reasons, including infections, medications and trauma. You can’t always prevent it, but in most cases, it’s temporary. Because parosmia is a symptom of so many conditions, it’s important to get an evaluation from a healthcare provider.
Last reviewed by a Cleveland Clinic medical professional on 08/09/2022.
Learn more about our editorial process.