The word Dysgeusia is of Greek origin, and it means bad taste. Dysgeusia or paraguesia is a medical condition which is characterised by a persistent, unpleasant, and metallic taste in the mouth due to an altered taste sensation. This altered taste can last from 3 months to years together, and in some cases when the damage to the olfactory nerves are severe, it can be permanent.
Causes of Dysgeusia
Dysgeusia is mainly attributed to zinc deficiency. It can also occur due to chemotherapy, dental procedure or an asthma treatment. Dysgeusia can also be an outcome of a wide variety of drugs. It can be a primary or a secondary illness. The duration of dysgeusia depends on the cause, and in most cases, it is only a temporary effect of a medical procedure.
The root cause of dysgeusia is the reduction of microvilli, saliva and the destruction of taste buds and damage of oral cavities all a side effect of radiation therapy for cancer. It is estimated that at least 50% of patients undergoing chemotherapy suffered from dysgeusia or another form of altered taste disease. The exact science behind the chemotherapy-induced taste impairment is still unknown.
Zinc is an important mineral, responsible for the production of taste buds in the mouth and tongue. Deficiency of zinc causes Dysgeusia. There are cases of bladder obstruction and dry mouth syndrome causing dysgeusia. Gastric disorders, diabetes mellitus, consumption of pesticides can also be contributing factors to this disorder. Menopausal women also experience it sometimes.
During pregnancy, usually in the first trimester, some women develop a metallic taste in the mouth. This is due to hormone fluctuations, and it usually goes away as the pregnancy progresses.
Nerve damage of the nerves connecting the taste buds and the brain can lead to a change in taste. The nerve damage usually occurs due to dementia, epilepsy, Bell’s palsy or multiple sclerosis.
Kidney failure can cause bad breath, loss of appetite and lead to a metallic taste in the mouth too. This is especially common in the case of people having diabetes.
The causes of dysgeusia can be any of the above. It can affect anyone with hormone imbalances for any duration of time. Medical science is yet to find the actual root cause of this disturbing condition but based on the symptoms and medical history of the patient, a diagnosis can be made, and treatment can be started.
Diagnosis of Dysgeusia
Taste-related disorders are generally tricky to diagnose and evaluate. Taste functions in the mouth are closely related to the sense of smell and pain, and it is difficult to separate one function from the other. The patient is generally questioned about symptoms, oral pain, ear infections, oral hygiene and stomach problems. The oral cavity, tongue and ear canal is examined (for sores) before medicines are prescribed.
Apart from this, with the advent of medical technology, several tests exist to determine if the condition is dysgeusia. Magnetic imaging is used to inspect the cranial nerves for lesions which might lead taste disorder. Electrophysiological tests are used to detect the abnormalities in the neurological makeup of the brainstem pathway. Chemical analysis of saliva is also performed as it part for the taste receptor environment. Electron micrograph which is nothing but an enlarged microscopic photograph of the taste buds are used to test for pathological disorders that diagnose dysgeusia.
Treatment of Dysgeusia
Because medical treatments have been directly responsible for around 20% of all dysgeusia cases, treatment for this cause has become very important. Below are some methods to treat this painful disease:
It has been found out that reduction of saliva is the root cause of dysgeusia among patients for whom this occurs as a side effect of some major treatment. To increase the saliva, several methods are employed. Intake of Acetylcholine can stimulate the salivary glands to produce more saliva. Saliva flow increases movement of the tastants towards the taste buds.
There was a recent study conducted in which zinc was infused with chemotherapy. However, since an excess of zinc can hamper immunity and imbalance the body physiologically, it is recommended to use this supplement treatment cautiously.
Altering the Prescription Drugs:
In many cases, as dysgeusia is a side effect of medical drugs, changing the regimen of the patient by prescribing alternate drugs often cures this disease completely. Some of the components in the drugs are chemicals which harm the ecosystem of the mouth and reduce saliva and damage taste buds, resulting in dysgeusia.
Alpha lipoic acid:
ALA or Alpha Lipoic Acid is an antioxidant which is present in a human cell. It is also found in yeast, red meats etc. and can be taken as a capsule. ALA also improves the nerve conduction velocity and reduces damage to human tissue. It is found to treat dysgeusia in the early trials and looks like a promising cure.
Home Remedies for Dysgeusia
To find a temporary respite from this condition, one can try below ways. It is however strongly recommended to visit a doctor.
- Regular dental care can help alleviate the symptoms. Brushing, flossing, and using a good mouthwash which is antibacterial might help give some relief.
- Chewing sugar-free gum can help to some extent as it keeps the saliva moving about in the mouth.
- Drinking water and other fluids regularly and throughout the day will disease keep you hydrated and improve body balance.
- Rinsing with a pinch of baking soda mixed in water can help to treat this condition.
Problems associated with Dysgeusia
The constant metallic, bitter taste in the mouth might lead to appetite loss. This can, in turn, lead to weight loss, malnutrition, depression and loss of immunity which can lead to a host of other issues. If it persists, it can be a sign of something more serious like a central nervous disorder like Parkinson’s disease or Alzheimer’s. Prompt treatment of this condition is usually advised.
If you are consuming one of the below drugs, they might be a cause of the metallic taste in your mouth too:
- Blood pressure meds
- Nicotine patches
- Diuretic medications
- Osteoporosis Medication
- Antihistamine medications
- Vitamins with high zinc, chromium or copper content
The above medicines must be avoided and can be replaced by the physician.
Coming to the daily diet, foods which are commonly not likeable for people suffering from a metallic taste are high-protein foods. White meats, cheese and eggs taste somewhat better. Chemotherapy often results in a taste aversion that tends to increase as the day progresses. Foods which are not very tasty should be consumed in the morning hours. Cold food is usually better received than hot foods by people with dysgeusia because lesser odours are emitted during cooking and eating of the food. If a patient persistently complains of a metallic taste in the mouth, then avoid using metal containers while cooking and instead use plastic utensils and containers.
To prevent inadequate intake of food which will cause a nutritional imbalance,the perception of taste can be enhanced by the addition of flavouring agents or extra spices to food. Studies have shown people in their old age tend to favour foods which have higher concentrations of salt, sugar and citric acid which is not preferable in the long run.
Apart from the above problems, Dysgeusia has a deep physiological impact as people who are afflicted by it are forced to manage this disorder which adversely affects the quality of life. People with this condition must ensure that they do not add excess salt and sugar to their food to compensate for the taste as that can adversely affect the health of the individual too. These taste distortions might cause other psychiatric problems which might require professional care.
Future research associated with dysgeusia
Every year more than 2 million people visit the doctor for treatment of this syndrome and sadly, this number is growing year on year. Hence many chemosensory institutes have been set up in the U.S.A and other countries to research and combat this problem. There are studies ongoing to find the underlying biological mechanisms involving taste so that this disease can be properly treated.
Immediate care and attention can cure dysgeusia completely and the majority of the time, it is temporary due to chemicals in the treatment which the patient is already taking. Immense caution must be exercised however as persistent bad taste in mouth can lead to several complications listed above.
This disorder is usually related to an age-related sensory loss, aggravated by medication or is a symptom of another disease. A diagnostic approach usually pinpoints the potential issues of gustatory dysfunction. This includes both issues in the mouth and central disorders.