Test Overview

A potassium test measures how much potassium is in the urine. Potassium is both an electrolyte and a mineral. It helps balance the amounts of water and electrolytes in the body. (Water is the amount of fluid inside and outside the body's cells.) It is also important in how nerves and muscles work.

Potassium levels often change with sodium levels. When sodium levels go up, potassium levels go down. When sodium levels go down, potassium levels go up. These levels are also affected by a hormone called aldosterone. This hormone is made by the adrenal glands.

Potassium levels can be affected by how the kidneys are working, the blood pH, and the amount of potassium you eat. The hormone levels in your body, severe vomiting, and taking certain medicines such as diuretics and potassium supplements can also affect the levels. Certain cancer treatments that destroy cancer cells can also raise potassium levels.

Many foods are rich in potassium. Some examples are tomatoes and tomato products, potatoes, figs, bananas, prune juice, orange juice, and squash. A balanced diet has enough potassium for the body's needs. But if your levels get low, it can take some time for your body to start holding on to potassium.

A potassium level that is too high or too low can be serious. Abnormal levels may cause symptoms such as muscle cramps or weakness, nausea, diarrhea, or frequent urination. Other symptoms may include dehydration, low blood pressure, confusion, irritability, paralysis, and changes in heart rhythm.