8 Symptoms of Kidney Failure You Shouldn't Ignore

3. Nausea

The most common of all gastrointestinal symptoms associated with end-stage renal disease are nausea and vomiting. The main reason they occur is that there's a rise in intestinal excretion of urea when the kidneys are malfunctioning. When urease (the enzyme that breaks down urea) acts on this increased urea, it leads to the production of excessive ammonia. Ammonia, in turn, stimulates the intestinal tract to produce a sensation of nausea, which—in people with more sensitive systems, may cause a vomiting spell as well. People with nausea and vomiting can have difficulty in consuming food and medications.