Serum Creatinine (Creatinine Level)

Why This Test Matters

Creatinine is a byproduct of muscle breakdown and is normally removed by your kidneys. High levels can indicate kidney problems, while low levels might suggest dehydration or muscle loss. This test is often used alongside other measures, like blood urea nitrogen (BUN), to evaluate kidney health.

What to Expect Before the Test

No special preparation is needed for this test. You may have a small needle inserted into a vein (usually in your arm) to draw blood. If you’re dehydrated, your doctor might advise drinking extra fluids the day before. Avoid strenuous exercise or heavy meals before the test.

What the Results Mean

Results are typically reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). While reference ranges vary by lab, higher than expected levels may signal kidney issues, while very low levels could raise concerns about hydration or muscle metabolism. Your doctor will interpret results in the context of your overall health.

Common Causes of Abnormal Results

High creatinine levels may be due to kidney disease, dehydration, or conditions that reduce blood flow to the kidneys. Low levels might result from overhydration, muscle wasting, or certain medications. Other factors, like diet (high-protein foods) or recent exercise, can also influence results.