Clen is not all its cracked up to be. I've only known 2 people out of dozen who has ever seen real results. Everyone is different, but from what I've seen, for the most part, your body gets use to it quickly or its just ineffective from the start. Before you know it you are taking higher does chasing the benefits, and if you aren't seeing the benefits from a low does, what happens is you just see more of the side effects and none of the benefits when you take higher doses. As cbbram mentioned Clen wasn't made for fat loss, it was made for people with asthma. I wouldn't touch it with a 10ft pole.