🧪 Creatinine Levels & Kidney Disease—What You Need to Know 💚 Creatinine is a waste product in your blood that comes from normal muscle activity. Healthy kidneys filter creatinine out of the blood—but when kidney function declines, creatinine levels rise. For people living with chronic kidney disease, creatinine is one of the most important kidney labs because it helps assess kidney function, track CKD progression, and calculate your eGFR. ✨ High creatinine may signal: • Reduced kidney function