The causes of a taste disorder

The causes of a taste disorder can be divided into three major groups. There are epithelial causes, nervous causes and central causes. Epithelial causes: Responsible for tasting are our taste organs, the taste papillae and the taste buds, which are not perceptible with the human eye.

If the taste organs are damaged, this is called an epithelial cause. The direct damage can be caused by various things such as drugs (penicillin, ACE inhibitors, cytostatic drugs used in chemotherapy and many other drugs).Irradiation, atrophic glossitis (inflammation of the tongue), hypothyroidism (hypothyroidism) and pernicious anemia (anemia caused by a vitamin B12 deficiency) are further epithelial causes of a taste disorder. Nervous causes: Nerve fibers are responsible for transmitting signals from the taste organs to certain areas in our brain so that we can taste anything at all.

If the nerves responsible for this (cranial nerve VII, IX or X) are damaged, this can manifest itself as a taste disorder. Damage to the nerves can occur unintentionally during ENT operations, through tumors, through fractures of the skull or through neuritis (inflammation of the nerves). Central causes: Among the central causes of a taste disorder are diseases such as the post-traumatic anosmia-ageusia syndrome (simultaneous loss of sense of smell and taste after a head trauma) or brain tumors.

There are a number of drugs that can lead to a disturbance of the sense of taste via different mechanisms of action. For example, antidepressants can lead to a pronounced dry mouth. Reduced saliva production can disturb the function of the taste buds of the tongue and make it less able to perceive tastes.

Other drugs, such as the antibiotic metronidazole, can also have a direct effect on the sensory cells and thus lead to a reduction in the sense of taste. Especially chemotherapeutic drugs, such as cisplatin, can lead to a complete loss of the sense of taste. Such a side effect is also caused by some drugs, which are mainly used in the treatment of high blood pressure.

These include ACE inhibitors such as enalapril, diuretics (especially hydrochlothiazide) and calcium antangonists (nifedipine). There are also drugs that cause us to perceive certain tastes that are not actually there. This is called dysgusia.

Examples of this are the drug allopurinol, vitamin D or many contrast agents that can produce a metallic taste on the tongue. However, most changes in taste caused by medication are not permanent side effects. It can usually disappear again by switching to another preparation or medication.

Side effects of antidepressants
Side effects of ACE inhibitor

One of the many side effects of taking cortisone is a change in taste. This is especially the case with higher doses, as used in shock therapy. Most patients who have taste changes under cortisone therapy report feeling a metallic or bitter taste in their mouth, which can be easily masked by sucking sweets.

This side effect usually lasts for several days after cortisone administration, but then disappears on its own. Most patients suffering from multiple sclerosis report sensory disturbances during the course of the disease. Approximately 5-20% of those affected have taste disorders.

This can be the result of damage to the area of the brain responsible for the perception of taste, but also of damage to the nerves responsible for taste and smell. The taste disorder mainly affects the perception of sweet and salty tastes. This symptom occurs in most patients in the course of a relapse and disappears in many patients in an early stage of the disease through a shock therapy with cortisone.

In most cases, a permanent reduction or loss of taste perception only occurs in a late stage of the disease. The occurrence of taste disorders is a rare complication that can occur during tonsillectomy. This is mainly due to the fact that during the operation the tongue is strongly pushed away, which can cause damage.

Furthermore, the taste buds in the area of the base of the tongue are strongly stretched during the operation. Usually the taste disorders after such an operation last only for a few days, because the nerve endings have to recover from the strong irritation. Only in very rare cases, there is a permanent reduction or even complete loss of taste perception. You can find more information about a tonsillectomy here.