Creatine with Kidney Disease: What You Need to Know

When you have kidney disease, a condition where the kidneys can’t filter waste properly, leading to buildup of toxins and fluid imbalances. Also known as chronic kidney disease, it affects how your body handles many substances—including supplements like creatine. Many people take creatine to build muscle or boost energy, but if your kidneys are already working harder than they should, adding extra stress isn’t something to take lightly.

Creatine, a naturally occurring compound made from amino acids that helps supply energy to muscles. Also known as creatine monohydrate, it’s one of the most studied supplements out there—and for good reason. It works. But when your kidneys are damaged, they may struggle to clear the increased creatinine levels that come from taking it. That doesn’t mean creatine is dangerous for everyone with kidney issues, but it does mean you need to know the difference between normal lab changes and real harm. Studies show that healthy people taking creatine don’t develop kidney damage. But in people with existing kidney disease, the data is mixed. Some small trials found no change in kidney function over 12 weeks, while others saw slight increases in creatinine that raised red flags. The key is: creatinine levels go up with creatine use—even if your kidneys are fine. That can trick doctors into thinking your kidneys are failing when they’re not.

Renal function, how well your kidneys filter blood and remove waste. Also known as kidney filtration rate, it’s the real measure of kidney health—not just creatinine levels. If you have kidney disease and are considering creatine, your doctor should check your eGFR (estimated glomerular filtration rate), not just your creatinine. A drop in eGFR over time is the real warning sign. A single high creatinine reading? Could just be the supplement. Many people with kidney disease also take other meds—like blood pressure pills or diuretics—that can interact with creatine. If you’re on multiple drugs, adding a supplement without checking in with your care team is risky.

What you’ll find here isn’t just a list of warnings. We’ve gathered real-world insights from people managing kidney disease who’ve tried creatine, along with clinical data on how it behaves in impaired kidneys. You’ll see comparisons with other supplements, what tests to ask for, and how to tell if it’s helping or hurting. No fluff. No fearmongering. Just what you need to decide—safely.