Creatinine Clearance (24-hour urine collection)

Why This Test Is Done

Your doctor may order this test if you have symptoms like fatigue, swelling, or frequent urination that could indicate kidney problems. It’s also used to monitor kidney function in people with diabetes, high blood pressure, or other conditions affecting the kidneys.

How the Test Works

You’ll collect all urine for a full 24-hour period in a special container. Your doctor will provide instructions to ensure accuracy. The urine is then tested for creatinine levels, while blood is drawn to calculate your creatinine clearance rate.

Sample Collection Process

Start by emptying your bladder into the container at the beginning of the 24-hour period. Collect all urine, including overnight, and discard the first morning urine if instructed. Replace the lid tightly and refrigerate if needed. Return the container to your doctor’s office or lab on time.

What to Expect After the Test

After the test, you’ll likely have a simple blood draw to measure creatinine levels. Results are used to determine how well your kidneys are filtering waste. Follow-up may include additional tests or lifestyle recommendations based on your results.