xenadrine is the bestest....the only side effect i notice is that in the morning at work i am a real dickhead..i get edgy and hyper. but it actually helps, because the people leave me alone and let me do my work. and the other thing that sucks is none of my suitpants fit and i dont wanna get the waist taken in because i know im gonna get all fat again this winter anyway....as long as you keep up the protein intake and calories, you will lose weight, but not muscle....that been my experience anyways....i have about a 4pack right now and never do cardio except running to catch the bus in the morning. highly recommended