A Acidosis (Over-acidification) describes an acidic pH value of the blood. The normal pH value of the blood fluctuates only very slightly between pH 7.36 and 7.44. In addition, the blood has a number of different buffer systems that ensure that the pH value remains within these limits, regardless of whether we ingest acids or bases through our food, for example, or whether we produce a lot of lactic acid due to physical exertion such as an endurance run (Lactate, an acid produced during anaerobic glycolysis). The acid-base balance is largely influenced by two major systems: breathing and our metabolism. Disorders in either of these systems can lead to acidosis.

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How the acid-base balance works

A “normal” pH value in our blood is very important, as all of our metabolic processes function best in this area. If over-acidosis develops, the metabolic processes cannot function properly.

Two major systems influence our acid-base balance: breathing and metabolism. Breathing influences the carbon dioxide (CO2) actuator: if we breathe deeper and faster, we exhale more carbon dioxide. Carbon dioxide reacts as acid in our blood (by reacting with water to form carbonic acid). In simple terms: the more and the deeper we breathe, the less acid there is in our blood and, conversely, if we only breathe shallowly or a little, more acids remain in our body and acidosis develops.

The second actuator is metabolism. With a normal diet, we consume more acids than bases every day. In order to maintain our fixed pH, we therefore have to excrete acids in the urine. If this is disturbed, we get acidosis. Our body also forms acids (such as lactic acid) during great physical exertion and when there is a lack of oxygen.


Acidosis can cause a variety of different symptoms. While slowly developing acidosis is often associated with little to no symptoms, acute acidosis shows pronounced symptoms. These can be disorders of consciousness with tiredness, headaches, memory disorders and changes in personality up to loss of consciousness (acidotic coma). Coordination disorders and trembling of the hands can also occur; in the case of mild acidosis, muscle weakness can also be in the foreground.

With mild acidosis, high blood pressure often develops, while with severe acidosis it is more likely to be accompanied by a drop in blood pressure. In addition, cardiac arrhythmias with slow heartbeat and palpitations (Arrhythmias) consequences. The bowel movement becomes less and it can lead to constipation and abdominal pain.

In addition to these general symptoms, depending on the cause of the acidosis, various symptoms can also appear. If the disorder is caused by an impairment of breathing (such as a lung disease), a particularly rapid impairment of consciousness can follow with the maximum form of the coma ("CO2 anesthesia"). If you get used to it for a long time due to chronic lung diseases, general symptoms such as fatigue, headaches, muscle weakness and hand tremors are more in the foreground.

If the acidosis is caused by the metabolism, other symptoms occur in addition to the symptoms mentioned above, which are caused by counter-regulation of breathing. To get rid of the extra acids from the body, those affected breathe deeper. This creates regular, particularly deep breathing, the so-called Kussmaul breathing. This breathing can partly normalize the pH of the blood.

Read more on this topic at: I recognize acidosis from these symptoms


The causes of acidosis are many. The division into problems with breathing and causes that lie in the metabolism of our body serves as a rough guide.
In the case of lung diseases that result in less shallow breathing or reduced gas exchange in the lungs, what is known as respiratory acidosis develops. Not only does the acidity of our blood increase, but there is also a lack of oxygen due to the reduced breathing.

This can happen through acute or chronic illness. The acute illnesses that can be associated with acidosis include, for example, pneumonia, acute lung failure or pulmonary embolism. Even with heart failure (Heart failure) breathing may be impeded by water being expelled from the blood vessels into the lungs. If you inhale toxic gases, the lung tissue can be attacked and inadequate gas exchange can result in over-acidification of the blood.
Another group of causes for respiratory acidosis are diseases of the muscles or nerves that supply the respiratory muscles and rib fractures, in which the pain causes less deep breathing. The use of opiates such as heroin, tranquilizers or large amounts of alcohol can also cause changes in the brain to slow breathing and thus also lead to acidosis.

Chronic lung diseases are very common causes of respiratory acidosis. Often this can occur due to a "smoker's lung" (COPD, chronic obstructive pulmonary disease), especially if lung function deteriorates due to an additional infection. A severe asthma attack can also be associated with hyperacidity. In general, acidosis can develop in any chronic lung disease.

The second large group are metabolic diseases (metabolic acidosis). Acidosis can occur here due to a lack of excretion or the increased uptake of acids. But even with metabolic processes in the body, more acids can be formed.

In the case of an unrecognized or poorly controlled sugar disorder (diabetes), as well as chronic alcohol addiction and prolonged starvation, the body tries to create other energy reserves. This creates so-called ketone bodies, which lead to acidification of the body. In all diseases that lead to a lack of oxygen in the body or that consume more energy, more lactic acid falls in the body (Lactate) on. This is also known from athletes for whom the lactic acid produced is measured in a fitness test. These diseases include e.g. Anemia, shock, various poisonings, seizures and heat stroke. In severe liver and kidney diseases, lactic acid cannot be excreted sufficiently. This is a common problem, especially with chronic kidney failure.

Renal failure

The acidosis can also be traced back to renal insufficiency. The kidney is an important metabolic organ, which is entrusted with the excretion of various metabolic products. In addition to waste products from the body's many metabolic processes, toxins are also excreted via the kidneys.

The kidneys also play an important role in regulating the acid-base balance, as they can retain or excrete acids in the body.The excretion of acids can be significantly slowed and reduced in kidney failure, which can cause acidic metabolic products to accumulate in the blood and cause or worsen acidosis.

Read more on the subject at: Symptoms of renal insufficiency

What is respiratory acidosis?

In the development of an imbalance of acids and bases in the body, a fundamental distinction is made between metabolic and respiratory disorders. The latter is based on a breathing problem. In addition to the uptake of oxygen, breathing also causes the exhalation of CO2 and thus has a significant influence on the acid-base balance of the body.

If breathing is restricted, carbon dioxide builds up in the blood, which leads to acidosis. Acidotic derailments can also be compensated for through breathing. This is the reason for the deep breathing that can occur with acidosis. This so-called reflective "Kussmaul breathing" causes an immediate increase in the pH value in the blood through increased exhalation of CO2.

Read more on the subject at: Respiratory acidosis

What is lactic acidosis?

Lactic acidosis is a dreaded acute metabolic disorder that can be associated with life-threatening consequences. It is a metabolic disorder that leads to an incorrect breakdown of glucose in energy production. In the cells of the body, the glucose can be converted into energy while consuming oxygen in order to maintain all organs and body processes.

Due to various causes, lactic acidosis can lead to a disturbance in the breakdown of glucose, which incorrectly results in the production of lactate (lactic acid) as a by-product. Lactate can build up in the bloodstream and cause significant acidosis. Lactate enrichment also plays an important role in sport. If the muscle cannot keep up with sufficient energy production with oxygen utilization, lactate is formed instead, which leads to rapid fatigue.

The lactate, also called "lactic acid", primarily leads to nausea, abdominal pain and the typical signs of acidosis with deep breathing. Later, even kidney weakness and a state of shock can occur, in which various metabolic processes can lead to a lack of blood volume in the entire body with considerable consequences for various organs.

Lactic acidosis is mainly triggered in patients with kidney or liver problems. Lactic acidosis is also typically found in diabetics, as the most common antidiabetic agents can cause the disease. Metformin, a drug used in type 2 diabetes, can cause lactic acidosis in rare cases.

Read more on the subject at: Side effects of metformin


Acidification that occurs suddenly represents an emergency situation and should therefore usually be treated in hospital.
Therapy for acidosis differs depending on the cause. If the acidosis is caused by an acute lung disease, ventilation is often required. This can improve gas exchange in the lungs. Thereafter, the underlying disease should be treated (e.g. with antibiotics for pneumonia).

If chronic lung disease worsens, it is often possible to work with drugs that widen the airways. "Emergency sprays" (inhaled betamimetics or anticholinergics) and cortisone preparations often help. A slight dose of oxygen can be given, but it should only be dosed in a low dose (0.5-1 liters per minute), since breathing worsens and even leads to unconsciousness (coma) threatens. In the case of chronic lung diseases, ventilation should be chosen more cautiously.

Read more on the subject at: Therapy of COPD

In the therapy of metabolic acidosis, the treatment of the underlying disease is in the foreground (e.g. therapy of diabetes, renal insufficiency, etc.). If the pH shifts very sharply to below 7.10, the pH value can be raised by infusing the base bicarbonate.


Acidosis is determined by a blood gas analysis. To do this, an arterial blood sample is taken (usually from an artery in the forearm) or a few drops of blood are taken from the earlobe after a vasodilator ointment has worked.

A detailed anamnesis discussion should reveal possible causes. To further determine the cause, various values ​​are determined in the blood and urine. In addition, the blood sugar level can be determined.

If the cause is respiratory-dependent, an X-ray examination of the lungs and various lung function tests are often performed. An examination in the sleep laboratory can also be useful.

Read more on the subject at: Blood gas analysis

Can you smell acidosis?

In principle, acidosis is a disease of the blood that can have serious consequences for the organs. Only when the adaptation of the metabolic processes involved in the acid-base balance results in products that are exhaled or excreted in some other way can acidosis also cause odors.

Typically, this process occurs in diabetics. The insulin deficiency in this clinical picture leads to an apparent lack of energy despite an increased glucose level in the blood, since the glucose cannot be absorbed into the cells. As a result, as in heavy fasting and starvation times, fat is burned with the formation of so-called "ketone bodies" to provide the cells with alternative energy. The ketone bodies can cause a typical acetone odor in the air you breathe, which can smell of nail polish remover or fermented fruit. Unconscious persons with a strong odor of acetone may suffer from severe diabetic derailment with acidosis and a coma that has already occurred.

Read more on the subject at: Diabetic coma

Consequences of acidosis

Acidosis can be associated with many metabolic changes and noticeable symptoms. It can be associated with serious life-threatening consequences, which is why the body tries to compensate for the acidosis with the help of various compensation mechanisms.

Direct consequences can be shortness of breath, deep breathing, blue lips, tiredness, fainting or coma. Due to metabolic processes that lead to the excretion of the acid, the amount of urine may be increased, weakness, muscle cramps and tiredness may occur and severe cardiac arrhythmias may occur. All of these are dangerous immediate consequences of acidosis. In extreme cases, if the acidosis cannot be compensated for quickly, life-threatening consequences such as shock, cardiac arrest or coma can occur.


In the case of acidosis, the prognosis depends heavily on the causal disease. Severe acidification is an emergency situation and should therefore be clarified by a doctor immediately. Some acute illnesses can completely disappear again with therapy, with some chronic lung illnesses only an improvement can be achieved.


Since acidosis is a symptom of various diseases, there is no general prophylaxis. The underlying disease should be treated and controlled (e.g. stopping sugar disorder diabetes). Many of the lung-dependent causes have nicotine as the main cause (especially in COPD). Therefore, completely abstaining from nicotine is the most important preventive measure for these diseases.

Acidosis in the baby

There are many health risks for mother and child during childbirth. The birth process is an enormous stressful situation, which can affect the metabolism and the vital functions of the child's organs. Not infrequently it can lead to metabolic derailments such as a child's acidosis.

One possible cause for this is a lack of oxygen in the newborn. This can result from umbilical cord incidents or adjustment problems after the birth. Due to the baby's lack of oxygen supply, lactate is created in the body's cells as an alternative source of energy in order to maintain vital body processes. The lactate can cause severe damage to numerous organs and tissues.

The central nervous system suffers most, in the worst case irreversible brain damage occurs. As a rule, babies can endure much more extreme pH values ​​than adults. Babies do not need to worry up to a pH of 7.2.

Acidosis in the urine

Acidosis in the urine is not uncommon in principle and is not a cause for concern. The pH value in urine is subject to strong fluctuations and is only partially related to the body's metabolic processes. While acidosis in the blood should be treated, the acidosis in the urine may resolve on its own within a short period of time and is not a disease.

Read more on the subject at: urine pH

The pH level in the urine is largely a matter of diet. Animal products such as meat, fish, eggs or cheese can metabolize acids which are excreted in the urine. Acids in the form of protons can also be released into the urine through various natural metabolic processes in the body or to compensate for acidosis in the blood. They are then excreted through this.

In addition, there is always a certain amount of uric acid in the urine, which is a natural metabolic product of the body. With permanently acidic urine, however, there is a slightly increased likelihood of developing uric acid stones, which can block the ureters. In order to treat these ureteral stones, the acid in the urinary tract can be reduced by adjusting your diet.

Fasting acidosis

Fasting affects the body in a similar way to acute diabetic derailment. Extreme fasting can cause the body to suffer an acute lack of energy because the body's glucose stores are depleted. As a result, the body attacks the reserves and breaks down fatty tissue, creating so-called "ketone bodies" as an alternative to the glucose molecules as a substitute energy source.

This metabolic process can lead to acidosis with loss of consciousness and a strong acetone odor like a diabetic coma. The only difference is that there is enough glucose in diabetes, which, however, cannot be absorbed into the body cells due to the lack of insulin.

Read more on the subject at: Risks of Fasting

How does potassium change in acidosis?

A typical consequence of acidosis is hyperkalemia. Behind this are metabolic compensation mechanisms that set in immediately in the case of acidosis. The body tries to eliminate excess acid from the blood in various ways.

One route of elimination takes place via the kidneys. In the kidney corpuscles, acid can be released into the urine in the form of protons (positively charged hydrogen atoms). The acid can then be excreted in the urine. The release of protons in the kidney has the consequence that potassium ions are reabsorbed back into the blood in exchange from the urine.

As long as acidosis persists, the potassium can build up in the body and cause severe symptoms. Initially, there may be abnormal sensations such as tingling or muscle weakness. However, greatly increased potassium levels can quickly lead to cardiac arrhythmias with irregularities and even cardiac arrest.

What is it about the hyperacidity theory?

In alternative medicine, the theory of hyperacidity is a common cause of many diseases. The alleged hyperacidity takes place in the kidneys and is said to be influenced by food and behavior. This overacidification is tested using urine pH test strips.

The theory of hyperacidity, however, has no scientific background. The body effectively balances out all fluctuations in the acid-base balance. Acid urine has no disease value and is subject to considerable fluctuations. The benefits of a so-called "basic" lifestyle have not been scientifically proven.