Dysgeusia is the medical term for an altered, distorted or reduced ability to taste.

Specific types of taste disorders include hypogeusia (a reduced ability to taste) and ageusia (an inability to detect taste). A persistent bad taste in the mouth (parageusia) is sometimes used interchangeably with dysgeusia.

Taste buds in the mouth can detect five basic taste sensations: sweet, sour, salty, bitter and umami (savory). Umami refers to glutamate, (such as monosodium glutamate or MSG), which is found in food products such as chicken broth, meat extracts and some cheeses. For more complex tastes, the sense of smell is required. Many taste disorders are actually associated with an impaired sense of smell, which can occur due to colds or other upper respiratory infections. Often, people do not discover they have a smell disorder until they notice a problem with taste.  

More than 200,000 people seek help for a taste or smell disorder every year, according to the National Institutes of Health. The actual incidence of these disorders is estimated to be in the millions because a large number of people do not seek help for the condition. Taste disorders can affect a person’s quality of life. It can lead to a decreased appetite, poor nutrition and the inability to identify potentially harmful foods or beverages.

Taste disorders can have many different causes. Various illnesses (e.g., colds, strep throat), lifestyle habits (e.g., smoking), irritants (e.g., insecticides, certain prescription mouthwash) and other factors (e.g., medications) can contribute to dysgeusia.

Patients are urged to contact their physician or dentist if they have a taste disorder that lasts two weeks or longer. A thorough medical history may be taken, including questions about symptoms, current medications and medical conditions, recent illnesses, and whether the patient’s sense of smell is affected.

The oral cavity may be inspected for any signs of infection, tooth decay or any other potential causes of dysgeusia. In some cases, x-rays may be taken. Tests that measure the extent of a person’s sense of taste or smell may be performed. If no underlying medical or dental condition is identified, the patient may be referred to a facility that specializes in taste and smell disorders.