Welcome to this Decision Guide about a blood test called creatinine. It's often abbreviated as "Cr."

Creatinine is usually measured to check a person's kidney function. Creatinine enters the bloodstream as a waste product of muscle metabolism. It is normally removed from the blood by the kidneys. When doctors check someone's creatinine, they are usually looking to see if it is normal (suggesting good kidney function) or high (as an indication of kidney disease or related problem). A low creatinine all by itself is usually unimportant.

Now, let's get to your test results.

To understand whether your creatinine is normal or not, it's helpful to ask you this question first:

Are you male or female?

I am female.

I am male.