Creatinine

Creatinine is a normal waste product in your body. It’s made when you use your muscles and some of the muscle tissue breaks down. Normally, your kidneys filter creatinine from your blood and remove it from your body in your urine. If there is a problem with your kidneys, creatinine can build up in your blood and less may be released in urine. If blood and/or urine creatinine levels are not normal, it may be a sign of kidney disease.