Dysgeusia: Symptoms, Causes, Diagnosis, and Treatment

Altered Sense of Taste

Dysgeusia is a taste disorder that causes foods to taste weird. In most cases, this altered sense of taste goes away on its own.

Dysgeusia can be triggered by a virus like COVID-19 or the common cold. It can also be a side effect of chemotherapy or other medication. Dysgeusia is common during pregnancy and with certain vitamin deficiencies. It typically goes away once the underlying cause has been resolved.

Dysgeusia is not dangerous or life-threatening, although it does impact your quality of life.

This article discusses dysgeusia symptoms and causes. It also explains how dysgeusia is diagnosed and treated.

Your sense of taste is activated all the time, but it is more sensitive while you are eating and within about an hour after eating.

Taste is mediated by taste receptors in your mouth. The receptors signal the facial nerve (cranial nerve seven), the glossopharyngeal nerve (cranial nerve nine), and the vagus nerve (cranial nerve 10). These nerves send signals to the sensory area of your brain, allowing you to recognize the taste. The taste sensation typically elicits a positive, negative, or neutral response.

A disruption in your sense of taste can result from damage or impairment in any part of this pathway.

An altered sense of taste can affect you while you are eating or drinking and even when you are not. Some people complain of a metallic taste, a bitter taste, a salty taste, or an unpleasantly sweet taste.

Dysgeusia can interfere with your enjoyment of all or some foods, but it rarely causes nausea. And dysgeusia often causes aversion to certain foods.

With dysgeusia, you may also experience other symptoms. These symptoms are typically related to the cause of your dysgeusia and are not caused by taste distortion.

Associated symptoms include:

Dysgeusia is a distorted sense of taste.

Ageusia is a total loss of taste.

Anosmia is a partial or total loss of smell, which can also affect your sense of taste.

Aliageusia is when things that usually taste good suddenly taste unpleasant.

Hypogeusia is when you have a hard time tasting sweet, sour, salty, or bitter flavors.

Phantogeusia is when you taste something bitter or metallic when eating something that should not contain those flavors.

People with gastroesophageal reflux disease often experience an altered sense of taste when stomach acid backs up into the throat. This can cause food to taste metallic.

There are numerous causes of dysgeusia. Some of these are related to changes in the mouth, such as a dry mouth, dental problems, or chemotherapy, while others are based on changes in the neurological aspects of taste sensation, such as pregnancy and migraines.

Common temporary causes of dysgeusia include:

There are hundreds of medications that can cause dysgeusia. Taking medicine that can cause taste distortion as a side effect does not necessarily mean that you will develop dysgeusia, however. You can develop dysgeusia with just a few doses, or it may come on suddenly after you have been taking the medication for years.

Some of the medications that are associated with dysgeusia include:

There are a number of medical conditions that result in an impaired sense of taste. Several of the medical conditions that interfere with taste sensation also interfere with the sense of smell, and it can be difficult to distinguish which of these senses is impaired.

Common medical illnesses associated with impaired taste sensation include:

Alzheimer's disease and other forms of dementia can cause an altered sense of taste. People with dementia sometimes develop new food preferences, which can include liking foods they previously did not like or disliking foods they once loved.

Chemical toxin exposure can impair your sense of taste. Chemicals in pesticides, cosmetics, detergents, and industrial environments can enter your system through your skin, mouth, or nasal passages.

Any traumatic injury affecting your mouth or the nerves that mediate your sense of taste can cause dysgeusia. This can happen due to an accident, surgery, or after a severe infection.

Some of the things that can cause this kind of nerve damage include:

Your sense of taste can also change as you get older.

You might develop a decreased appetite when you experience dysgeusia for a short time. You may lose weight, even if this problem lasts for only a few days.

In fact, pregnant women who experience dysgeusia often lose several pounds. However, in a healthy person, appetite is restored once dysgeusia resolves, and most people regain their weight.

When taste distortion is caused by a long-term condition, such as diabetes, gastrointestinal (GI) disease, or a stroke, it can result in malnutrition. Some people lose weight permanently.

With dysgeusia, you can develop a preference for unhealthy foods, which results in malnutrition—even without weight loss.

The diagnostic evaluation of dysgeusia is based on determining whether you have an altered sense of taste and identifying the cause.

There are several diagnostic tests that can be used to evaluate taste. Some of the examinations involve measuring your response to exposure to certain tastes. Other tests evaluate your nerve function.

You may need one or more of the following diagnostic tests for evaluation of your taste distortion:

If your taste distortion seems to be related to a problem with your sense of smell, you might have one of the following diagnostic smell tests:

You might need to have blood tests to identify nutritional deficits caused by dietary changes if your dysgeusia has caused you to avoid food.

It is important that you are tested for nutritional deficiencies if you have dysgeusia for longer than a few months. Often, nutritional effects are not easily detected within the first few weeks.

Tests that are used to identify a nutritional deficit include a complete blood count (CBC) to assess your red blood cells (RBC) count. Specialized blood tests can measure your vitamin B12, iron, calcium, and potassium levels.

You may also need to check your lead or mercury levels to identify a toxic exposure to either of these agents.

If there is a concern that you could have a growth, infection, or a structural issue in your mouth, throat, or brain, you would need to have an imaging test, such as an X-ray, computerized tomography (CT), or magnetic resonance imaging (MRI) to assess the area of concern.

The treatment of dysgeusia can include a few approaches, and you may need a combination of these strategies. If you have a nutritional deficit, this has to be addressed and corrected.

A few treatments can help reduce your sense of taste distortion. And if a cause of your taste distortion is identified, you would also need treatment for the cause of your taste disorder.

Typically, vitamin and mineral deficiencies can be corrected with supplements. If you have a major deficiency, you may need to take a prescription-strength supplement as directed by your healthcare provider.

A few strategies can be used to help diminish your altered sense of taste. Some healthcare providers and dentists suggest using artificial saliva products.

Sometimes, good oral hygiene, including flossing, brushing, and regular use of mouthwash can alleviate the effects. In fact, if the overgrowth of oral bacteria is the cause of your dysgeusia, taking care of your oral health can permanently resolve the problem.

Your healthcare provider may recommend dietary modifications to help reduce the unpleasant taste in your mouth or to alleviate a GI condition.

For example, some experts suggest eating food with a few ingredients so that the tastes do not become mixed together, potentially causing an unpleasant effect. Sweetened food, preservatives, and heavily spiced food can leave an unpleasant residue in your mouth, so it is a good idea to avoid these products.

Dietary strategies can help alleviate some GI conditions. For example, fiber and raw fruit and vegetables can combat constipation. And if you have any food intolerance, the resulting bad breath can exacerbate your dysgeusia.

Several of the causes of taste distortion, such as pregnancy and the common cold, resolve on their own.

If your smoking habit is the cause of your dysgeusia, then smoking cessation can help. If you are taking medication that causes dysgeusia, your healthcare provider might change your prescription.

You may need treatment to correct the cause of your taste distortion. For example, constipation can be managed with diet and stool softeners. Allergies can be managed with antihistamines or steroids.

Taste changes due to conditions such as Alzheimer’s dementia are not treatable, and the issues with altered taste need to be addressed as effectively as possible to help improve appetite and nutrition.

Dysgeusia is a type of taste disorder that causes food to taste different than it should. It is often caused by a temporary condition such as a cold, allergies, or pregnancy. Sometimes, however, it is caused by something long-term such as dementia or Parkinson's disease. Chemical exposure and nerve injury can also cause dysgeusia.

Dysgeusia usually resolves on its own, but you may need additional therapies such as nutritional supplementation or a change in diet. In many cases, treating the underlying cause will make the dysgeusia go away.

Dysgeusia is often mild, but it can be distressing. This condition can affect your enjoyment of food and it may bother you even when you aren’t eating. You should talk to your healthcare provider if you experience a distorted sense of taste that lasts for longer than a few days.

Try to be observant about any other symptoms that you are experiencing. And carefully consider whether you might have been exposed to any new substances around the time that your dysgeusia developed—these observations can help you and your medical team as you work to identify the cause of your problem. Once you know the cause of your taste distortion, you and your healthcare provider can begin to work on a treatment plan.

Yes. Problems with smell and taste, including an altered sense of taste, are common symptoms of COVID-19. They are also considered symptoms of long COVID, which refers to symptoms that persist for four or more weeks after a person is infected with the coronavirus.

Yes. Deficiencies of vitamin B, especially B12, and certain minerals like zinc can lead to changes in how food tastes. Supplements usually return your sense of taste.

If the underlying problem can be treated or resolved on its own, you should regain your sense of taste. In some cases, such as dysgeusia caused by chemotherapy or COVID-19, it may take months for your sense of taste to return to normal.

Paxlovid mouth is a side effect of COVID-19 medication. It has been described as a metallic or disgusting taste similar to grapefruit gone bad or garbage left baking in the hot sun.

Paxlovid combines two medications—nirmatrelvir and ritonavir. Experts suspect the bad taste is caused by ritonavir, an HIV treatment with a side effect of dysgeusia.

Dysgeusia from Paxlovid typically lasts the course of the five-day treatment and resolves on its own.

No, dysgeusia can be extremely unpleasant, but it is not life-threatening. It is typically temporary, but can impact your quality of life while it lasts.

Matsunaga K, Yoshida Y, Takemaru M, et al. Multidisciplinary clinical approach by sharing oral examination information to treat a diabetes patient with dysgeusia. Clin Case Rep. 2019;7(5):877-880. doi:10.1002/ccr3.2111

Carvalho BF, Alves MG, Dutra MT, Balducci I, Nicodemo D, Almeida JD. Persistent dysgeusia post-halitosis treatment: How does it impact the patients' quality of life? Med Oral Patol Oral Cir Bucal. 2019;24(3):e319-e325. doi:10.4317/medoral.22370.

Schambeck SE, Crowell CS, Wagner KI, et al. Phantosmia, parosmia, and dysgeusia are prolonged and late-onset symptoms of covid-19. JCM. 2021;10(22):5266. doi:10.3390/jcm10225266

American Academy of Otolaryngology–Head and Neck Surgery Foundation. Dysgeusia.

Carvalho BF, Alves MG, Dutra MT, Balducci I, Nicodemo D, Almeida JD. Persistent dysgeusia post-halitosis treatment: How does it impact the patients' quality of life? Med Oral Patol Oral Cir Bucal. 2019 May 1;24(3):e319-e325. doi: 10.4317/medoral.22370.

Matsunaga K, Yoshida Y, Takemaru M, Yamashiro K, Monden I, Inohara K et al. Multidisciplinary clinical approach by sharing oral examination information to treat a diabetes patient with dysgeusia. Clin Case Rep. 2019 Mar 22;7(5):877-880. doi: 10.1002/ccr3.2111. eCollection 2019 May.

By Heidi Moawad, MDHeidi Moawad is a neurologist and expert in the field of brain health and neurological disorders. Dr. Moawad regularly writes and edits health and career content for medical books and publications.