24-Hour Urinary Creatinine Clearance

What Does This Test Measure?

Creatinine clearance calculates the volume of blood your kidneys filter per minute (or over 24 hours). It combines results from your blood creatinine level and the amount of creatinine excreted in your urine. This helps determine how efficiently your kidneys remove waste products from your bloodstream.

Why Is This Test Done?

Your doctor may order this test if you have symptoms of kidney disease (such as fatigue, swelling, or frequent urination), if you have a history of kidney problems, or if you’re taking medications that can affect kidney function. It’s also used to monitor chronic conditions like diabetes or high blood pressure.

How Is This Test Performed?

You’ll collect all urine for a full 24-hour period in a special container. At the start and end of the period, your blood will be drawn to measure creatinine levels. The test requires precise timing and accurate urine collection to ensure accurate results.

What Are Common Results?

Results are typically reported as a clearance rate (e.g., in milliliters per minute or liters per day). Lower than expected values may indicate kidney dysfunction, while higher values could suggest overhydration or other conditions.