Ageusia is a medical term for the loss of taste. Temporary or persistent, partial or total, loss of taste can have many origins but is often associated with loss of smell (anosmia).

Ageusia is a taste disorder characterized by the loss, decrease or absence of the sense of taste. It is due to an alteration of various sensory receptors, including the taste buds. It can be considered as:

• total ageusia when characterized by loss of perception of the five flavors: sweet, salty, bitter, sour and umami;
• partial ageusia, also called hypoageusia, when the loss of taste affects only certain flavors.

Ageusia can have many explanations but it is often associated with anosmia, that is to say a loss of smell. It is for this reason that health professionals sometimes evoke the anosmia-ageusia syndrome.

With or without anosmia, ageusia can be caused by:

• nerve damage, particularly at the level of the glossopharyngeal nerve;
• facial paralysis ;
• a trauma ;
• a respiratory tract disorder, especially during a cold or pneumonia;
• inhaling toxic substances ;
• aging, which can induce an alteration of sensory receptors;
• le tabagisme ;
• cancer ;
• chemotherapy and radiotherapy ;
• taking certain medications including certain calcium channel blockers, antiarrhythmics, anti-epileptics, copper chelators or, more rarely, certain hypoglycaemic agents.

Ageusia results in a decrease or loss of taste. It is often associated with a loss of smell (anosmia).

While ageusia does not constitute a direct health risk, it can have harmful consequences when it persists.

In the long term, the loss of taste can induce:

• of the eating disorders, such as anorexia or bulimia, which are due to the lack of pleasure when tasting a dish;
• a feeling of unease, which can manifest as a decline in morale, interest and motivation, and which can lead in the most serious cases to depressive disorders, withdrawal into oneself and isolation.

Ageusia with anosmia may constitute a security problem. The loss of taste and smell limits or even prevents the detection of certain warning signals, such as a bitter taste in the mouth or a smell of smoke.

Diagnose ageusia

Treatment of ageusia depends on the origin of the loss of taste. The diagnosis can be made by a general practitioner, or an otolaryngologist in case of ageusia with anosmia. To confirm or deepen a diagnosis, certain medical tests can be carried out. An electrogustometry examination can in particular be carried out to analyze the origin of the loss of taste.

Treat ageusia

Depending on the diagnosis, several solutions can be considered to treat or limit ageusia. For example, drug treatment may be prescribed when the anosmia-ageusia syndrome is due to a respiratory tract infection. Complications of loss of taste can also be limited by learning, recognizing and rehabilitating foods.

Prevent ageusia

It is possible to prevent the occurrence of certain forms of ageusia and anosmia by limiting certain risk factors. In particular, it is recommended to:

• do not smoke or quit smoking;
• to maintain a healthy and balanced diet.