for potassium in the urine is a test that
checks how much potassium is in the urine. Potassium is both an
electrolyte and a mineral. It helps keep the water
(the amount of fluid inside and outside the body's cells) and electrolyte
balance of the body. Potassium is also important in how nerves and muscles
Potassium levels often change with sodium levels. When
sodium levels go up, potassium levels go down, and when sodium levels go down,
potassium levels go up. Potassium levels are also affected by a hormone called
aldosterone, which is made by the
Potassium levels can be
affected by how the
kidneys are working, the blood pH, the amount of potassium you eat, the
hormone levels in your body, severe vomiting, and
taking certain medicines, such as diuretics and potassium supplements. Certain cancer
treatments that destroy cancer cells can also make potassium levels
Many foods are rich in potassium, including scallops,
potatoes, figs, bananas, prune juice, orange juice, and squash. A balanced diet
has enough potassium for the body's needs. But if your potassium levels get low, it can take some time for your body to start holding on to potassium. In the meantime, potassium is still passed in the urine, so you may end up with very low levels of potassium in your body, which can be dangerous.
A potassium level that is too high or too low can be
serious. Abnormal potassium levels may cause symptoms such as muscle cramps or
weakness, nausea, diarrhea, frequent urination,
dehydration, low blood pressure, confusion,
irritability, paralysis, and changes in heart rhythm.
Why It Is Done
A urine test to check potassium levels
is done to:
- Look for the cause of a low blood potassium test result (hypokalemia).
How To Prepare
You do not need to do anything before
having this test.
Talk to your doctor about any
concerns you have regarding the need for the test, its risks, how it will be
done, or what the results will mean. To help you understand the importance
of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
Urine potassium can be checked in a
single urine sample but it is more often measured in a 24-hour urine
Urine collection over 24 hours
- You start collecting your urine in the
morning. When you first get up, empty your bladder but do not save this urine.
Write down the time that you urinated to mark the beginning of your 24-hour
- For the next 24 hours, collect all your urine.
Your doctor or lab will usually provide you with a large container that holds
about 1 gal (4 L). The container has a small amount of preservative in it.
Urinate into a small, clean container and then pour the urine into the large
container. Do not touch the inside of either container with your
- Keep the large container in the refrigerator for the 24
- Empty your bladder for the final time at or just before the
end of the 24-hour period. Add this urine to the large container and record the
- Do not get toilet paper, pubic hair, stool (feces), menstrual
blood, or other foreign matter in the urine sample.