Potassium urine test
The potassium urine test measures the amount of potassium in urine.
How the Test is Performed
After you provide a urine sample, it is tested in the lab. If needed, the health care provider may ask you to collect your urine at home over 24 hours
. Your provider will tell you how to do this. Follow instructions exactly so that the results are accurate.
How to Prepare for the Test
Your health care provider may ask you to temporarily stop any medicines that may affect the test results. Be sure to tell your provider about all the medicines you take. These may include:
- Nonsteroidal anti-inflammatory drugs (NSAIDs
- Potassium supplements
- Water pills (diuretics)
Do not stop taking any medicine before talking to your doctor.
How the Test will Feel
This test involves only normal urination. There is no discomfort.
Why the Test is Performed
Your doctor may order this test if you have signs of a condition that affects body fluids. This may include dehydration, vomiting, or diarrhea.
It may also be done to diagnose or confirm disorders of the kidneys or adrenal glands
Other conditions for which the test may be ordered include kidney cysts
(medullary cystic disease).
The usual range for a person on a regular diet is 25 to 125 mEq/l per day. Lower or higher urinary levels may occur depending on the amount of potassium in your diet and the amount of potassium in the body.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
Higher than normal urine potassium level may be due to:
- Diabetic acidosis
and other forms of metabolic acidosis
- Eating disorders (anorexia, bulimia)
- Kidney problems, such as damage to kidney cells called tubule cells (acute tubular necrosis
- Low blood magnesium levels (hypomagnesemia)
- Use of non-potassium-sparing diuretics
Low urine potassium levels may be due to:
- Certain medicines, including beta blockers, lithium, trimethoprim, potassium-sparing diuretics, or nonsteroidal anti-inflammatory drugs (NSAIDs)
- Adrenal glands
releasing too little hormone (hypoaldosteronism)
There are no risks with this test.
Gerber GS, Brendler CB. Evaluation of the urologic patient: history, physical examination, and urinalysis. In: Wein AJ, Kavoussi LR, Novick AC, et al., eds. Campbell-Walsh Urology. 10th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 3.
McPherson RA, Ben-Ezra J. Basic examination of urine. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 28.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.