Any type of enhancing things like that is bad news. It gives you a false sense of accomplishment. Once you stop using it, you will loose what you have gained while on it.
The best way to get bigger and stronger is by eating healthy, exercising, and you can also take vitamins too.
Natural is the best, safest, and healthiest way to go. Supplements don't replace natural by any means. It doesn't even come close.
I don't know what the side effects are, or even if it's addictive, but you can google that.