
Originally Posted by
cmax
Creatine is not hard on the liver, however it can be hard on the kidneys and the stomach. However, this is only a real factor with long-term or extended creatine use, don't use creatine for over 45 days because at this point it becomes less effective and you need to give your body time to recover.
Being hard on the kidneys and stomach does not necessarily mean that it will cause any permanent damage - it just means that it might give you a stomach ache or might accelerate the formation of already developing kidney stones. But usually the later is also due to other factors such a dehydration or a predisposition to kidney complications.