What are the side effects of creatine?

Creatine monohydrate has been shown in numerous studies to be, safe, even in large quantities (Robinson, et al 2000), nevertheless there are some side effects of creatine which you need to be aware of before commencing its use.

Due to its effect on fluid balance after consuming creatine it can cause mild irritation to the stomach and nausea for a short while. This is particularly apparent during the loading phase. Whilst this is a little unpleasant, it is harmless and minimised if you consume plenty of fluid. For this reason I also wouldn't recommend you use creatine at times when you are prone to feeling a little sick, e.g. immediately after training or first thing when you wake up.

Quite intense muscle cramps have been reported in many athletes who supplement with creatine, which could lead to injuries, and impair performance. Muscle cramps tend to be more prevalent in more energetic sports like athletics and football, rather than bodybuilding.

Some users have reported headaches, but again, drinking plenty will help prevent this side effect.