Phosphate in Urine
How It Feels
There is no pain while collecting a 24-hour urine sample.
There is no chance for problems while collecting a 24-hour urine sample.
The phosphate urine test measures the amount of phosphate in a sample of urine collected over 24 hours (24-hour urine test). Phosphate is a charged particle (ion) that contains the mineral phosphorus.
The normal values listed here-called a reference range-are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Results are usually available in 1 to 2 days.
Phosphate in urine
0.4-1.3 grams (g) per 24-hour urine sample
13-42 millimoles (mmol) per day
Calcium- and phosphate-restricted diet:
Less than 1.0 g per 24-hour urine sample
Less than 32 mmol per day
Many conditions can change phosphate levels. Your doctor will talk with you about any abnormal results that may be related to your symptoms and past health.
High urine phosphate levels may be caused by:
Low urine phosphate levels may be caused by:
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
What To Think About
- Phosphate may also be measured in the blood. To learn more, see the topic Phosphate in Blood.
- Results of a test to measure phosphate in urine are seldom useful on their own. They should always be interpreted along with the results of other tests.
- The loss of too much phosphate into the urine may cause conditions that damage the bones, such as rickets or osteomalacia.