When used orally at appropriate doses, creatine is likely safe to take for up to five years. However, there is concern that creatine taken in high doses is possibly unsafe and could damage the liver, kidneys or heart. There isn't enough evidence to recommend use of oral creatine as a heart failure treatment. People also use oral creatine to treat certain brain disorders, congestive heart failure and other conditions. There are many protein powders to choose from, so we've compiled some of the best options to help you choose the right one for you.