As reported previously, an excess of urea in the blood stream has been linked to the development of high blood pressure in certain patient populations. While urea is a common metabolic waste product and is normally broken down by the liver and then excreted by the kidneys, various conditions and problems can cause this normal cycle to malfunction, leading to a buildup of urea in the body.
Eliminating excess urea when the normal body mechanisms have stopped working correctly is a complicated and challenging problem, with very few safe and effective treatments. The New England Journal of Medicine, however, reports this week on a promising new therapy for eliminating excess urea in these situations.
The treatment, which uses of a combination of two chemicals called sodium phenylacetate and sodium benzoate, does not work to decrease the levels of urea directly. Instead, it acts to decrease the amount of urea produced by channeling ammonia - a major source of urea - into other biochemical pathways. By using this approach, the new treatment capitalizes on the fact that while the body's ability to excrete urea is diminished, it is not gone. A lower level of overall urea production decreases the demands on the excretion system, and allows the body to "catch up," resulting in an ultimate decrease in the amount of urea present.
The drug, which is administered intravenously, has recently been approved by the FDA and is marketed under the name Ammonul.