Medical expert of the article
New publications
Sour taste in the mouth
Last reviewed: 04.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Often, a sour taste in the mouth can make itself known after eating some sour food.
However, if the appearance of a sour taste has nothing to do with the characteristics of food, occurs frequently and is combined with other unpleasant symptoms, then, most likely, we are talking about a disease. Only a specialist can establish an accurate diagnosis. We will try to describe the main possible causes of this condition.
Causes sour taste in the mouth
The reasons for a sour taste in the mouth can be very diverse:
- excess acidity of gastric juice;
- disrupted function of the digestive system;
- pathologies of the oral cavity (inflammation of the periodontium or gums, caries);
- taking certain medications.
If a sour taste appears in the mouth, you should pay attention to the function of the pancreas. If this symptom is combined with heartburn, then the underlying factor may be reflux esophagitis - the reflux of stomach contents into the esophagus.
Often, a sour taste appears in pregnant women - this can be explained by the reflux of acid from the stomach cavity into the oral cavity due to the pressure that the growing uterus exerts on the digestive organs.
If a sour aftertaste is combined with dryness in the mouth, then one can suspect a violation of the water balance (electrolyte metabolism), or insufficient fluid intake.
A sour taste with bitterness can be a consequence of eating large amounts of smoked foods, unhealthy and fatty foods, which, in turn, leads to problems with the liver and biliary system.
Why does a sour taste appear in the mouth?
If there are any changes in taste sensations or if an incomprehensible and unusual taste occurs, you should consult a doctor. Only a specialist can adequately answer this question, having conducted all the necessary studies. If the sour sensation is combined with abdominal pain, bouts of nausea and vomiting, an upset stomach, then it is imperative to examine the digestive system immediately. These symptoms may be a manifestation of gastric ulcer and duodenal ulcer.
Inflammation of the stomach walls with increased acidity is a very common factor in the occurrence of a sour taste in the mouth. In order to prevent further progression of the disease, it is necessary to switch to a proper gentle diet. It may be necessary to prescribe some medications that will be prescribed by a gastroenterologist.
[ 3 ]
Sweet and sour taste in the mouth
If a sweet and sour taste appears in the mouth, this can be considered a sign of the following conditions:
- consequences of a stressful and conflict situation, or depression, when the amount of sugar in the bloodstream increases;
- consequences of abuse of large amounts of sweets and sugar;
- diseases of the digestive system, liver;
- consequences of abruptly quitting smoking;
- diseases of the oral cavity associated with excessive proliferation of bacterial microflora (gingivitis, periodontitis, caries);
- intoxication with chemicals (pesticides, carbonic acid dichloride - phosgene);
- side effects when using certain medications.
In some cases, a sweet and sour taste in the mouth may indicate asymptomatic diabetes.
Bitter-sour taste in the mouth
A bitter-sour taste in the mouth may bother you only occasionally, or be present constantly. However, the reasons do not always indicate any disease: sometimes it is simply a consequence of our bad habits. A bitter-sour sensation in the mouth may appear:
- in the morning, if a lot of fatty and fried foods were eaten in the evening. In this case, the liver and digestive system took on an excessive load, which did not have the best effect on the functionality of the organs;
- after drinking alcohol, especially in large doses, which increased the load on the gallbladder, liver and stomach;
- after antibiotic therapy or taking antiallergic drugs, which resulted in disruption of the digestive tract;
- in heavy smokers, especially when smoking at night.
If we consider possible diseases with a bitter-sour taste in the mouth, then in most cases these can be lesions of the digestive tract and biliary tract: cholecystopancreatitis, gastric ulcer and duodenal ulcer, gastritis and cholecystitis.
Sour metallic taste in the mouth
A metallic taste in the mouth is often associated with the appearance of blood in the mouth. However, this sensation can often be caused by metal crowns and dentures, which in some cases emit this aftertaste.
However, most often, a sour-metallic taste in the mouth is associated with the following reasons:
- oral diseases (periodontosis, stomatitis, gingivitis);
- chronic intoxication, poisoning with mercury, lead, zinc, arsenic, copper compounds;
- initial stage of diabetes mellitus;
- hormonal surges during puberty, pregnancy, menopause, etc.;
- bleeding stomach ulcer;
- chronic anemia.
In addition, changes in taste sensations can be caused by the use of certain medications, such as antibiotics, anticonvulsants, nonsteroidal anti-inflammatory drugs, anticholinergics, and cardiovascular drugs. In this case, the sour-metallic taste completely disappears after discontinuing the drug.
[ 6 ]
Sour and salty taste in the mouth
A sour-salty taste in the mouth may indicate inflammation of the salivary glands - sialoadenitis. However, the cause may often be more banal: the same taste appears with prolonged crying, a runny nose, and other otolaryngological diseases.
The production of sour-salty saliva may be a sign of systemic Sjogren's disease, which is manifested by chronic damage to the salivary and lacrimal glands.
A sour-salty taste in the mouth can also be caused by nutritional disorders:
- drinking large amounts of strong coffee and strong black tea;
- alcohol abuse;
- consumption of large amounts of energy drinks, cola, lemonade and other carbonated drinks;
- insufficient fluid intake, dehydration;
- overeating combined with little fluid intake.
However, most often the appearance of a sour-salty taste indicates not one problem, but a combination of them: for example, a simultaneous lesion of the digestive system along with inflammation in the nasal cavity, or a stomach disease due to poor nutrition.
Nausea and sour taste in the mouth
If nausea and a sour taste in the mouth appear at the same time, this clearly indicates problems with the digestive system. Later, the condition may be supplemented by a feeling of heaviness in the epigastric region (in the projection area of the stomach), pain in the upper abdomen, belching, etc. The cause of such a pathology may be:
- gastritis with high acidity;
- peptic ulcer of the stomach and duodenum;
- gastroduodenitis.
In addition, nausea and a sour taste can be a consequence of overeating - eating too much food, as well as eating dry food: food simply stagnates in the stomach, causing nausea and a sour taste. Later, rotting and fermentation processes in the stomach can begin, which will manifest as "rotten" belching, upset stool, vomiting.
However, most often nausea and a sour taste indicate damage to the pancreas, which can only be confirmed by a special examination of the entire digestive system.
Sour taste in mouth in the morning
If you have a sour taste in your mouth in the morning, it is most likely the result of a heavy dinner the night before: the food simply did not have time to digest, stagnation occurred, which only manifested itself in the morning. This is especially possible if the dinner was not only heavy, but also accompanied by fatty, fried or smoked food, as well as alcohol. This combination of products is especially heavy on the digestive system, and when we go to bed, we force the digestion processes to slow down, which causes stagnation of food masses in the stomach. Moreover, after eating, we take a horizontal position: the stomach is full, and part of its contents and gastric juice are partially thrown into the esophagus and from there into the oral cavity. As a result, in the morning we have a sour taste in the mouth.
If such a condition is repeated periodically, it means that its occurrence is not accidental. It is necessary to suspect problems with the digestive system, in particular, gastritis or gastroduodenitis, as well as gastroesophageal reflux.
Sour milk taste in the mouth
If the taste of sour milk in the mouth is not associated with the recent consumption of fermented milk products, then the following diseases and conditions can be suspected:
- consequences of recent stress;
- helminthic invasion;
- intestinal spasm;
- problems with the digestive system.
Stomach and pancreas disorders can often lead to a sour milk taste in the mouth. However, as a rule, diseases are not limited to just one symptom: nausea, belching, and abdominal pain may also be observed. Vomiting attacks and loose stools are rare, but general weakness, fatigue, and drowsiness can often be observed. In most cases, such signs are symptoms of gastritis or pancreatitis, which requires mandatory consultation with a gastroenterologist or therapist.
Constant sour taste in the mouth
If the sour taste in the mouth is constant, then we can talk about the presence of some diseases in the body. In this case, you should definitely consult a doctor and find out the cause of this symptom. There can be quite a few reasons:
- hyperacid gastritis – inflammation of the stomach walls against the background of increased acidity of gastric juice. Characteristic signs of this disease: constant sour taste in the mouth, pain in the abdomen, periodic nausea, heartburn, sour belching;
- gastroesophageal reflux – partial return of gastric juice into the lumen of the esophagus, which over time causes irritation of the mucous membrane of the esophageal tube and the development of an inflammatory process – esophagitis;
- gastric ulcer and duodenal ulcer - with this disease, the sour taste may not always persist, but only during the acute stage of the disease;
- diaphragmatic hernia – weakening or increased elasticity of the diaphragm opening, which allows gastric acid to enter the esophagus;
- oral diseases - dental caries, periodontal disease, gum disease. With these diseases, the balance of microflora in the oral cavity is disturbed, which leads to a shift in the acid-base balance of the oral cavity to the acidic side;
- pancreatitis is an inflammatory process in the tissues of the pancreas.
In addition, a prolonged or constant sour taste in the mouth may be associated with the intake of nicotinic acid, with the predominant consumption of sweets and sugar, with insufficient fluid intake in the form of pure water.
Sour taste in mouth during pregnancy
The main reason for heartburn and sour taste in the mouth during pregnancy is considered to be hormonal changes in the woman's body. During pregnancy, the level of progesterone, a sex hormone produced in large quantities by the corpus luteum, increases significantly. The hormone is necessary to reduce the tone of smooth muscles in order to prevent contraction of the uterine muscles and involuntary termination of pregnancy. However, along with the uterine muscles, other organs with a smooth muscle structure also relax. These organs include, in particular, the stomach, the gastric sphincter and the esophageal tube. When relaxed, the sphincter begins to pass the contents of the stomach back into the esophagus: this is how acid from the stomach ends up in the oral cavity.
There is another reason for a sour taste in the mouth during pregnancy: this is the progressive enlargement of the uterus, which over time begins to squeeze nearby organs, including the stomach. Under the influence of pressure, stomach acid can partially flow into the esophagus, which provokes the appearance of a sour taste in the mouth. The situation can worsen if the pregnant woman overeats or lies down to rest immediately after eating. This condition is often combined with heartburn and a sore throat.
Who to contact?
Treatment sour taste in the mouth
It is not advisable to treat a sour taste in the mouth without medical advice. You can take independent measures if the sour taste has occurred several times and is not permanent. What should you do?
- Establish a diet: do not overeat, do not eat unhealthy, fatty, smoked and fried foods, eat more often, but in small portions.
- Eat more plant foods, cereals, and less sweets, buns, processed foods and fast food.
- Drink enough liquid in the form of pure water, green tea, freshly squeezed juices. You should exclude sweet sodas, cola, energy drinks, strong tea and coffee.
- Stop smoking and drinking alcohol, including beer.
- Maintain good oral hygiene, brush your teeth regularly and visit the dentist.
- It is not recommended to lie down immediately after eating: you should sit or walk in the fresh air. For the same reason, it is not recommended to eat at night.
At the first sign of acid in the mouth, you should not drown it out with a solution of baking soda: at first, this may really help, but in the future the problem will only get worse, and the consequences can be very dire.
If the above recommendations do not help, and the sour taste in the mouth does not go away, you should contact a specialist: a therapist, gastroenterologist or dentist. The doctor will determine the true cause of acid in the oral cavity and prescribe treatment for the underlying disease.