What is secreted by the kidney?

The kidney secretes several substances into the urine. These include:

- Ammonia

- Bicarbonate

- Hydrogen ions (protons)

- Potassium ions

- Magnesium ions

- Creatinine

- Urea

- Uric acid

The kidney also excretes various drugs and toxins and other waste products produced by cells and tissues throughout the body.