Taste Disorder: Causes, Symptoms & Treatment

A taste disorder, or tasting disorder, manifests as an impairment in the experience of taste. A healthy lifestyle can sometimes help reduce the risk of developing the disorder.

What is a taste disorder?

In medicine, taste disorder is also known as dysgeusia. In this context, the term taste disorder encompasses several forms of disorders of taste sensation:

First, taste disorder is divided into the so-called qualitative and quantitative taste disorder. Experts speak of a qualitative taste disorder when it is not the quantitative expression of the taste sensation that is disturbed, but rather the nature of the taste sensation: For example, qualitative taste disorders include the sensation of taste impressions although no corresponding taste stimulus (e.g. food) is present. This is referred to as phantogeusia. If, on the other hand, a taste is experienced that is not adequate for the underlying object, this is referred to as parageusia. A quantitative taste disorder, on the other hand, is when the expression of the taste sensation is disturbed; hypergeusia describes an increased, hypogeusia a restricted taste experience. In ageusia, there is a complete loss of taste.

Causes

The causes of a taste disorder can be varied. In most cases, a taste disorder develops over time; in rare cases, a taste disorder may be congenital. Among the causes of a taste disorder, a distinction is made between the so-called nervous, central and epithelial causes:

A nerve-related taste disorder is usually based on damage to various cranial nerves that are involved in the sensation of taste. This can happen, among other things, during operations in the head region or as a result of fall injuries. Central causes (affecting the central nervous system) of a taste disorder can be caused by injuries to the brain or various neurological, degenerative diseases. If epithelial (affecting the covering and glandular tissue) causes of a taste disorder are present, inflammatory or viral processes, for example, but also side effects of medications may be present. Another cause of taste disorders could be the novel coronavirus disease (COVID-19). Physicians from different countries point out this new symptom in corona infection.

Symptoms, complaints, and signs

Taste disorders can come in different shapes and forms. Symptoms depend on how long the disorder has been present and its underlying causes. Basically, taste disorders are expressed by the fact that the affected person perceives tastes and, in some cases, odors in a different way. In some people, there is a complete loss of the sense of taste, while others perceive stimuli more intensely. Some patients perceive a particular stimulus differently and can no longer clearly identify the taste of onions, for example. In individual cases, a taste is perceived that is not present. This is often accompanied by noticeable sensory disturbances in the area of the mouth and tongue. Those affected then feel numbness or even tingling in the mouth. The symptoms of a taste disorder often appear suddenly and persist for weeks, months or even years. In most cases, they can be quickly alleviated by drug treatment or they even spontaneously resolve on their own. Accompanying symptoms do not usually occur with a taste disorder. However, the altered taste sensation is perceived as very unpleasant by those affected. If the symptoms are severe, there is a loss of appetite and, as a consequence, undesirable weight loss.

Diagnosis

The diagnosis of a taste disorder is initially based on the descriptions of an affected patient. Thus, a physician usually first inquires whether there is a restriction of the sense of taste and how pronounced such a restriction is. The physician may also inquire whether the impaired sense of taste in the context of a taste disorder relates only to certain tastes or to the entire spectrum of tastes. In this way, among other things, the nature of a present taste disorder can be defined more precisely.After obtaining the information from the patient, further diagnostic procedures are common; these include taste tests and examination of the mouth and throat. Depending on the cause of a taste disorder suspected by the physician, procedures may also be used that reveal brain waves that occur when a taste stimulus is presented (for example, EEG).

Complications

Taste disturbance can have different causes, which can result in various complications. For example, influenza may cause the disturbances. In the course, bacteria can infect the body in addition to the underlying disease, leading to otitis media (inflammation of the middle ear). Sinusitis or bronchitis are also possible. One of the most feared complications includes bacterial pneumonia. Furthermore, the heart is also heavily stressed by the flu, so that cardiac arrhythmias can be added. Diabetes mellitus can also be causative for taste disorders. Long-term elevated sugar levels can lead to vascular occlusion, which subsequently causes damage to certain organs. The kidneys are frequently affected and may fail in the course of the disease (diabetic nephropathy). Disturbances in the electrolyte and water balance are the consequences. The vessels in the eye are also frequently affected. This can lead to impaired vision, which can even result in blindness (diabetic retinopathy). Nerves can also be damaged, the affected person then usually gets disturbances in sensitivity. This can lead to the patient no longer feeling pain, especially in the foot. Wounds can thus no longer be felt, which can spread and lead to death of the foot.

When should you go to the doctor?

A doctor should be consulted as soon as the affected person registers changes in his taste perception. If he notices that his taste sensation differs significantly from that of his peers, a visit to the doctor is advisable. If there is numbness of the tongue or hypersensitivity to food, a doctor should be consulted. If the taste disorder makes it impossible to recognize toxic and hazardous substances, it is necessary to consult a doctor. In many cases, everyday life can be managed well even with a taste disorder. Nevertheless, a medical examination is necessary to determine the extent and cause of the disorder. This is the only way to prevent future misbehavior and to take the impairment into account. If symptoms such as sudden vomiting, nausea or dizziness occur immediately after a food intake, a doctor should be consulted. Consultation with a physician is also required if stomach pain or digestive tract impairment occurs. In case of diarrhea or constipation, a medical check-up should be done to ensure that no further impairments occur. If the affected person suffers from headaches, cramps or a general feeling of malaise, a visit to the doctor is necessary. If there is a diffuse feeling of pain, pressure in the chest or a feeling of fullness, a visit to the doctor should be made to clarify the cause. If psychological problems occur due to the taste disorder, a doctor is also needed.

Treatment and therapy

Effective treatment of a taste disorder first requires a detailed diagnosis. In this way, the cause behind a taste disorder can be specifically treated. If a qualitative taste disorder is present (i.e., a taste disorder that manifests itself in the fact that an affected person has a qualitatively altered sense of taste or perceives tastes without the presence of a real taste carrier), there is a high chance that the symptoms will disappear on their own after approximately 12 months. Therapeutic successes are also recorded here, for example, after the therapeutic administration of zinc or so-called alpha-lipoic acid, which are supposed to help combat the corresponding insensations. If the qualitative taste disorder is caused, for example, by taking medication (this can manifest itself, for example, as a bitter or metallic taste), discontinuation of the corresponding medication usually leads to a rapid recovery of the original taste sensation. If a taste disorder is caused by inflammatory processes in the oral cavity (due to poor oral hygiene or infections), treatment with antibiotics may be effective.

Outlook and prognosis

The prognosis of taste disorder depends on the present cause. If the taste buds in the tongue have been destroyed due to a burn, relief of symptoms occurs within a few days or weeks. The organism can regenerate dead taste buds, so that freedom from symptoms can be expected after a short time. In the case of damage to the nerve pathways, it must be determined whether this is regenerative or irreparable. Permanent impairment of the nerve fibers leads to lifelong impairment of taste perception. If paralysis is present, for example, recovery is no longer possible. If a tumor disease is present, the prospect of recovery from the taste disorder also decreases. The benign or malignant tumor must be completely removed before the symptoms can be alleviated. In some cases, the taste disorder is subsequently regenerated as the taste buds form anew. In principle, however, the prognosis for cancer depends on the individual circumstances and the overall diagnosis of the patient. A cure is not always possible. In the case of a traumatic disorder, relief of taste perception is linked to the success of the therapy and the cooperation of the patient. Normally, improvement in health occurs once the emotional distress is processed or cognitively reevaluated.

Prevention

Effective prevention of a taste disorder can occur primarily by positively influencing the possible causes. For example, consistent oral hygiene can help prevent inflammation or impairment in the oral cavity. Responsible management of underlying conditions present that may lead to a taste disorder can help reduce the risks of developing a taste disorder.

Follow-up

Follow-up care for a taste disorder usually proves to be relatively difficult. In this regard, the taste disorder also cannot always be completely treated, so in some cases the affected person will have to rely on lifelong treatment or live with the disorder for the rest of his or her life. However, the patient’s life expectancy is not reduced or otherwise limited by this disorder. In some cases, medication can be taken for a taste disorder, and taking zinc in particular can have a positive effect on the course of this disorder. The affected person should therefore ensure that this medication is taken regularly, and of course possible interactions with other medications should also be taken into account. In cases of doubt, a doctor should always be consulted. Furthermore, proper oral hygiene can also reduce or completely remove the taste disorder. Affected persons should therefore always brush their teeth and, if necessary, also use a mouth rinse. This is the only way to alleviate the discomfort. If the taste disorder is treated with the help of antibiotics, it should be noted that these should not be taken together with alcohol. Furthermore, contact with other sufferers of this disease can also prove useful. In doing so, it is not uncommon for information to be exchanged.

What you can do yourself

The affected person can do some amounts, depending on the cause of the disease, to obtain relief or even cure of the symptoms. If the taste disorder is triggered by an unhealthy lifestyle, a change in food and an avoidance of toxins and harmful substances can contribute to recovery after only a few weeks or months. If a genetic disease or damage to the nerves is present, a cure for the taste disorder is rather unlikely. In these cases, the affected person should, for the purpose of self-help, adapt his lifestyle in such a way that he avoids important sources of danger. With the failure of the taste system, an important natural warning signal of the organism is not available to him. This must be taken into account when eating food. Attention should be paid to the temperature, appearance as well as the smell of the food before it is distorted. In this way, burns in the mouth or the ingestion of spoiled food can be avoided. If there is any doubt about the quality of the food, the advice of a trusted person should be sought.Since taste warns against ingesting foods that are too spicy, it is advisable to avoid products with a strong spicy content as a matter of principle. This prevents discomfort and stomach and intestinal problems.