Loss of taste (ageusia): duration, still a sign of Covid?

Ageusia refers to the partial or total loss of taste. It is one of the symptoms suggestive of Covid, more observed in recent weeks. In autumn/winter 2023, “the proportions of certain symptoms, such as ageusia and anosmia, appear higher in the group’JN.1‘ (under BA.2.86/Pirola lineage)”, indicates Public Health France in the risk analysis of November 13, 2023.

What is the definition of ageusia?

L’ageusia is a medical term that corresponds to the loss of one of the five senses: taste. It manifests itself by a partial absence (in most cases) or total (very rare) of taste when we deposit a substance on our sensory cells (which are located mainly on the tongue (the taste buds) and the soft palate). Concretely, a person suffering from ageusia has great difficulties to recognize the foods she eats and perceive their flavors. Note that this is the illness suffered by the famous gastronomic critic Charles Duchemin (played by Louis de Funès) in the film “L’Aile ou la Cuisse”.

Causes of loss of taste

Ageusia is due to an alteration of the taste receptors on the tongue, the soft palate and/or the wall of the pharynx. This alteration can be caused by:

• A nerve injury, occurring following a head trauma orfacial paralysis (due to a stroke for example).
• Taking certain heavy treatments such as radiotherapy or chemotherapy.
• Poor condition of the mouth and teeth.
• Gougerot-Sjögren Syndrome, an autoimmune disease of connective tissues, characterized by insufficient production of certain glands.
• Taking medications such as angiotensin-converting enzyme inhibitors (used for high blood pressure, coronary heart disease or chronic heart failure).
• An infection (a mycosis or a tumor) of the upper respiratory tract, mouth, tongue, particularly in ENT cancer.
• Excessive inhalation of toxic substances (tobacco, alcohol, drugs, etc.)
• Old age.
• Psychiatric disorders (hallucinations).

A suggestive sign of Covid?

Loss of taste (along with loss of smell) are also among the symptoms mentioned by patients with Covid (especially long Covid). These signs were reported during “mild forms of coronavirus and mainly in young people” indicated the government at the start of the epidemic. Now, time has shown that loss of taste can affect anyone. “The proportions of certain symptoms, such as ageusia and anosmia, appear higher in the group ”JN.1” than in the “other BA.2” group. 86”, but these differences will need to be confirmed“, explains Public Health France in its risk analysis on emerging variants of November 13.

Ageusia is manifested by loss of taste, partial or total. Concretely, the person cannot recognize food or to determine the flavor of what she eats : if it is salty, sweet, sour or bitter… People who are agueus sometimes say they have the impression of “chew cardboard or paper“. Loss of taste is often accompanied bya loss of smell (medically called anosmia). This can be a significant source of frustration and ultimately lead to eating disorders such as anorexia or bulimia as well as deficiencies (anemia).

How long does ageusia last?

The duration of loss of taste varies from one person to another and depending on the severity of the disease. To date, scientific studies have shown that ageusia lasts on average 11 days for patients over 40 years old and 6 days for patients under 40 years old.

When to worry and who to consult?

It is advisable to seek the advice of your treating physician by telephone or not via teleconsultation, if you notice a sudden loss of taste or smell. Even more so if this loss of olfactory and taste sensations accompanied by other symptoms (runny nose, cough, feeling of tightness in the sinuses, stuffy nose, body aches, difficulty breathing, etc.). It is not recommended to resort to self-medication “without specialist advice from your doctor or ENT”, would like to clarify the SNORL. Only health specialists can define whether or not the patient should take a specific treatment.

To establish the diagnosis of ageusia, the doctor questions the patient about their history, their eating habits, their possible allergies, their possible tobacco consumption and their possible medication intake, etc. are also checked. nasal breathing, oral hygiene and tongue condition to see if the lingual papillae are normal. The general practitioner can refer his patient to an ENT specialist who will be able to carry out a complete ENT examination. Additional examinations (chemical gustometry or electrogustometry) may be necessary to determine precisely which parts of the language are affected. Finally, it is sometimes necessary to carry out a neurological examination to check that there is no nerve damage.

Even if it can persist in many people, ageusia is not permanent and may be reversible, according to a study published in the scientific journal JAMA Otolaryngology Head & Neck Surgery on November 9, 2023. According to the authors of the article, the sense of smell and taste eventually, slowly but surely, returns. Treatments to relieve ageusia are possible, but limited. They are prescribed on a case-by-case basis and go through:

• Changing oral hygiene,
• Stopping smoking
• Antifungal treatment against possible infections,
• The use of artificial saliva (particularly in cases of Gourgerot-Sjögren Syndrome)
• Modification of drug treatment.

On the other hand, during ageusia due to the alteration of sensory cells caused by nerve damage or old age, the loss of taste can be permanent and no treatment can be effective.