Calcium (Ca) in Urine
A test for calcium in urine is a 24-hour test that checks the amount of calcium that is passed from the body.
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.
Test results may be affected by the amount of calcium in the diet.
Calcium in urine
| Low amount of calcium in diet:
Less than 150 milligrams (mg) per day or less than 3.75 millimoles (mmol) per day
| Average amount of calcium in diet:
100–250 mg per day or 2.5–6.2 mmol per day
| High amount of calcium in diet:
250–300 mg per day or 6.2–7.5 mmol per day
High values of calcium in the urine may be caused by:
In some cases, calcium in the urine may be high for other reasons. One example of this is idiopathic familial hypocalciuric hypercalcemia.
Low values of calcium in the urine 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:
- Eating or drinking too much or too little calcium before the test. For the best results, follow the instructions on how much calcium to have before the test.
- Taking medicines, such as diuretics. Many medicines can affect calcium levels in the blood.
- Not collecting 24 hours' worth of urine.
- Being on bed rest for a long time.
What To Think About