How can we reduce urea in the blood

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urea (Carbamide) is the main breakdown product of proteins (proteins) in the body. Determining it helps doctors assess the kidney function of a patient, but only to a limited extent because the measured value is an imprecise parameter. Find out here how urea is produced, which measured values ​​in the blood and urine are considered normal and what to do in the event of a deficiency or excess of urea in the blood.

What is urea

Urea - also called carbamide - is produced when protein building blocks (amino acids) are broken down in the liver. This initially produces toxic ammonia, which in higher concentrations mainly damages the brain. For this reason, the body converts most of the ammonia into non-toxic urea, which is then excreted through the kidneys and, in small amounts, through stool and sweat.

In agriculture, urea is used as a fertilizer because the high nitrogen content is essential for plant growth. In pharmacy, urea is used, among other things, as an antifungal agent for nail fungus: the active ingredient softens the infected nail so that it can be peeled off. Urea is also found in various drugs such as oral anti-diabetic drugs.

When is urea determined?

Since the urea in the blood only increases when the filter function of the kidneys is only 25 percent or less, it is not suitable as a routine parameter. Urea is therefore primarily used to diagnose and monitor the progress of kidney failure (renal insufficiency). The measured value can also be used to estimate how much protein someone is consuming (increased measured values ​​for a high-protein diet). This is especially important in the case of kidney disease.

Possible symptoms of elevated urea levels are tiredness, headache, fever, increased or decreased urination, or pain. Together with other parameters, an increased urea concentration is an indication for renal replacement therapy and provides information about its effectiveness.

Urea reference values

Depending on age, the following normal blood urea values:

When are the urea levels too low?

Since urea is produced during the metabolism of amino acids, the most common reason is a reduced protein intake. If the body produces more proteins (for example in late pregnancy or childhood), low urea levels also occur. Liver damage should also be considered. Enzyme defects in the urea cycle are extremely rarely responsible for low urea levels. They lead to death early.

When are the urea levels too high?

Theoretically, the level of urea in the blood increases as soon as the filtration capacity of the kidney decreases. However, since this only occurs when there is a loss of function of more than 25 percent, urea is considered a very inaccurate kidney parameter. Possible reasons for declining kidney function include kidney diseases such as inflammation or sclerosis. Medicines can also attack the kidneys under certain circumstances. Another possible cause is reduced blood flow to the kidneys as a result of heart failure, shock, or blood loss. If the urine flow is obstructed by stones or tumors, the urea levels also rise.

Increased urea levels as a result of an increased intake of protein with food are much safer. If the body becomes dehydrated, elevated urea levels are also measured.

Urea itself is non-toxic, but in high concentrations it can lead to headache, tiredness, vomiting and severe tremors. Increased levels of urea in the blood therefore always give reason for further diagnostics.

What do you do when urea is high or low?

If the urea is low, there is usually nothing to worry about. The deficit can easily be made up with protein-rich foods, such as eggs, meat, fish and legumes, as well as dairy products.

Increased urea is far more relevant. The cause should be found and remedied as quickly as possible. Renal replacement methods (dialysis) such as hemofiltration are used to reduce acute urea levels in the blood. Such a blood wash is indicated when the urea is more than 200 mg / dl in the blood.

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