Dysgeusia is the medical term used to describe any decrease or changes in taste. This can appear from birth or develop throughout life, due to infections, use of certain medications or due to aggressive treatments, such as chemotherapy.

In addition to taste changes, depending on the cause of dysgeusia, other symptoms may also appear, such as sneezing, fever, runny nose, sore throat and even facial paralysis.

If you suspect dysgeusia, especially when there are other symptoms, it is important to consult your general practitioner for an evaluation. Appropriate treatment depends on identifying the cause and may involve the use of anti-allergy medications and corticosteroids, for example.

Main symptoms

The main symptoms of dysgeusia are:

Feeling a bad taste when tasting foods that usually have good taste
No longer feeling salty or sweet tastes in foods with these characteristics
Feeling a bitter or metallic taste when you put food in your mouth
Sensation of different tastes in the mouth without having eaten

Furthermore, depending on the cause of dysgeusia, other symptoms may also appear such as toothache, facial paralysis, runny nose, sneezing or fever. If your experience dysgeusia, especially if it presents with other symptoms, it is important to consult a general practitioner for assessment.

Confirming a diagnosis

Dysgeusia is normally identified at home by the person themselves when they notice changes in taste. However, a medical evaluation is important to confirm the diagnosis, and tests may be ordered to assess the sensitivity of smell and taste.

Furthermore, depending on the suspected cause of dysgeusia, blood tests may also be ordered, such as vitamin tests or specific antibodies, as well as imaging tests, like a CT scan or MRI.

Types of dysgeusia

According to its characteristics, dysgeusia can be classified into some of the following types:

Ageusia: loss of the ability to taste
Hypogeusia: reduced ability to taste food or specific types of food
Hypergeusia: increased sensitivity to any type of flavor
Parageusia: feeling the wrong taste of a food
Phantogeusia: also known as "phantom taste", is the sensation of a flavor in the absence of actual food in the mouth

The specific type of dysgeusia identified depends on the changes that the person reports.

Possible causes

The most common causes of dysgeusia are:

Aging: older adults tend to have a reduced tasting ability and have more difficulty recognizing flavors;
Respiratory infections: COVID-19, flu and colds, for example, can affect the sensitivity of the taste buds and the transmission of taste sensations to the brain;
Allergies: like allergic rhinitis can affect the perception of flavor;
Use of medications: some medications such as antifungals, antibiotics and antihypertensives, for example, can alter the sensation of taste;
Alcohol: can alter saliva production and the sensitivity of the taste buds
Uncontrolled diabetes: high blood sugar levels can affect the nerves, and causes changes in taste;
Ear, mouth or throat surgeries: may cause some minor trauma to the nerves in their respective areas, affecting taste;
Chemotherapy and radiotherapy: changes in taste are a very common side effect of these types of cancer treatment, especially in cases of cancer in the head or neck region.

Furthermore, dysgeusia can also be caused by rheumatological diseases, such as systemic lupus erythematosus and Sjögren's syndrome, and neurological diseases. It can also be the sequelae of a stroke, Alzheimer's and Parkinson's.Therefore, identifying the cause of dysgeusia is essential for guiding the best treatment approach.

Could a change in taste be COVID-19?

Loss of smell and taste are two common symptoms of COVID-19. Dysgeusia in theses may also be accompanied by is other symptoms such as fever, cough and sore throat. Read more about the symptoms of COVID-19 and how it is transmitted.

Generally, taste and smell return within a few weeks of the infection, but in some people, it may take up to 1 year for taste to return totally to normal.

Treatment options

Treatment for dysgeusia depends on the underlying cause. It may be necessary to eliminate alcohol, and to use anti-allergy medications and/or corticosteroids. The doctor may also suspend the use of medications.

In some cases, like when dysgeusia is caused by aging, chemotherapy or surgery, it may be beneficial to consult a registered dietitian to provide suggestions on the best ways to prepare food for optimal taste.

It is also important to maintain adequate oral hygiene and to brushing your teeth and tongue at least twice a day to avoid bacterial build-up that can alter taste sensations.