Urine quantity

With reduced urine excretion, the first possible cause is an existing lack of fluid. This means that too much liquid is consumed in relation to the amount of drinking. This can happen, for example, with athletes or people who do heavy physical work (e.g. construction workers, metallurgical workers). Especially at very high temperatures, their fluid loss in the form of sweat exceeds their fluid intake. But diarrhea or vomiting can lead to this effect due to the associated loss of fluid. Another possibility is that those affected simply did not drink enough. Especially older people often lose the feeling of thirst and drink too little, so that unconsciously a lack of fluid manifests itself in their body.

If these systemic reasons for a reduced amount of urine can be ruled out, the cause may lie at the level of the kidneys or the urinary tract. Renal insufficiency, i.e. a loss of function of the healthy kidney, is possible. This leads to a decrease in the production of urine. Another cause of too little urine can be a lack of urine. In this case, although enough urine is produced, the outflow is disturbed. Causes of a urinary congestion can be kidney stones, an enlarged prostate or a urethral narrowing.

Another possible cause of the production of small amounts of urine throughout the day may be a disorder of the cardiovascular system. In heart failure, the heart is too weak to pump enough water through the bloodstream to the kidneys. As a result, the body stores more water in the tissue instead of excreting it. Much of the water collects you in your legs due to gravity. Therefore, a nocturnal urge to urinate is characteristic for these patients, since the sleeping position promotes the removal of water from the legs.

If more than three liters of urine are excreted a day, it is called polyuria. If a lot has been drunk, especially diuretic drinks such as coffee, black tea or alcohol, this increased amount of urine is normal. If this is not the case, other causes should be clarified.

The most common causes of increased urine production are:

• Diabetes mellitus (type I and II): The body excretes large amounts of urine, in which a lot of glucose is typically found. If too much sugar is in the blood, glucose is excreted via the kidneys with the urine. Patients with unrecognized or poorly adjusted diabetes mellitus experience a correspondingly strong thirst due to the large water loss and drink a lot (polydipsia)
• Diabetes insipidus: In this disease, a part of the control circuit that controls the water balance is disturbed. This leads to an increased excretion of water via the kidneys
• A disturbed electrolyte balance is another possible cause. The body tries to compensate for this by increasing the excretion of water. Polyuria occurs with a very salty diet, too much calcium or too little potassium in the blood
• Chronic renal insufficiency: when the kidneys are no longer able to concentrate the urine and thus much more water is excreted than in healthy kidneys
• After acute kidney failure, when the kidneys function again and produce a lot of urine as compensation
• Tumors in the area of the posterior hypothalamus, a part of the brain that regulates the body’s water balance
• Drugsthat have a flooding effect (diuretics)
• Bartter syndrome, a hereditary defect in a section of the kidneys