Creatinine

Used to evaluate kidney function, often together with eGFR.

To evaluate kidney function and the estimated glomerular filtration rate.

1. Check in advance whether you need to fast or have your blood drawn at a specific time.
2. Eating an unusually large amount of cooked meat or intense exercise before the blood draw can affect the result. Whether you need to fast depends on the order and the laboratory's rules.
3. Before the blood draw, avoid unusually intense physical exercise unless your doctor has advised otherwise.
4. Tell your doctor and the laboratory staff about any medicines and dietary supplements you take.

Fasting is often not necessary for this test alone. If other tests have also been ordered, or your doctor has prescribed specific preparation, follow the agreed rules.

A specific time is generally not required. If your doctor has set a different time, follow those instructions.

• Food, hydration or physical exercise, depending on the specific analyte
• Certain medicines or dietary supplements
• Hemolysis and delayed sample processing

Venous blood — serum or plasma, depending on the method

The blood sample is collected by a qualified staff member. The tube type, required volume, and processing and storage conditions are set by the laboratory's specific method. You do not need to store the sample yourself.

A raised creatinine may point to reduced kidney filtration, but muscle mass also affects the result. eGFR is often needed.

If your result is outside the reference interval, you have symptoms, or your condition changes, contact your doctor. If symptoms are severe or develop quickly, seek emergency care.

Do not stop treatment on your own. Confirm the final test conditions with the laboratory.