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Understanding Creatinine

Creatinine is a waste product made by normal muscle activity. Your kidneys remove it, so doctors use it as a rough signal of kidney filtering.

Why creatinine matters

A higher creatinine often means the kidneys are filtering less well, but the number is not perfect on its own.

That is why doctors usually interpret creatinine together with eGFR, urine protein, symptoms, and your prior baseline.

What can affect creatinine

  • Muscle mass
  • Hydration level
  • Recent illness
  • Certain medications
  • Kidney function itself

What high or low creatinine can mean

Higher creatinine may suggest reduced kidney function, dehydration, or another temporary stress on the kidneys.

Lower creatinine is often seen in people with lower muscle mass. It does not automatically mean the kidneys are healthier.

Creatinine makes more sense in context

Tracking creatinine alongside eGFR, urine protein, blood pressure, and medications gives a much clearer kidney picture.

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