Creatine supplements can be purchased over-the-counter, and are often used to enhance muscle performance for both athletes and people with degenerative health conditions. However, the supplements are not safe for everyone. Because they can affect the way water is absorbed in the body, they can cause kidney problems when taken in excess. In addition, creatine supplements are not appropriate for people who already have kidney disease.
Creatine Defined
Not to be confused with creatinine, which is a waste product of muscle breakdown, creatine is an amino acid. Creatine is found in many foods and is also produced naturally in the body. According to the University of Maryland Medical Center, creatine is created by the pancreas and the kidneys. Both naturally occurring creatine and that found in foods, such as meat and fish, is stored in the body's muscles where it is readily available for use as fuel. Muscles need creatine in order to function optimally, which has made it a popular supplement for athletes. Creatine may enhance athletic muscle performance for some people.
Creatine Supplements
There is some evidence, though limited, that creatine can improve athletic muscle performance for short bursts of activity during sports like sprinting. However, athletes are not the only ones whose muscles may benefit from extra creatine. People with chronic diseases that affect muscle performance may also find supplements appealing. According to Medline Plus, creatine is "possibly effective" in increasing muscle strength and endurance in people with heart disease, Parkinson's disease and muscular dystrophy. It has also been used for conditions such as chronic obstructive pulmonary disease and rheumatoid arthritis; however, there is little evidence that it improves function for these disorders.
Creatine and the Kidneys
Medline Plus warns that creatine can cause kidney damage in high oral doses; however, it does not clarify how high the dose has to be before it is considered potentially dangerous. The University of Maryland Medical Center cites a report in which an athlete taking 10 grams of creatine per day over a period of several weeks ended up in kidney failure. However, there is little other guidance out there when it comes to dietary supplements. While creatine is available over-the-counter, that does not mean it is safe for everyone.
Creatine Interactions
Creatine can also interact with other potentially kidney-damaging medications, causing a double impact. Medline Plus warns against combining creatine supplements with over-the-counter NSAID painkillers such as ibuprofen and naproxen. In addition, diuretics and gout medication can interact with creatine, potentially leading to kidney damage. Anyone who already has kidney damage or chronic kidney disease should also avoid creatine supplements unless advised by a doctor: While the risks are not completely understood, it is better to be safe than to risk further damage. Always discuss any dietary supplements with your doctor before adding them to your daily routine.
