I m on Vyvanse (30mg), and as a highschool student, it s working wonders after dealing with ADD for so long. As an athlete however, it s a nightmare. I was always a semi-skinny kid, so I started lifting in 8th grade. Now as a junior, and taking vyvanse since my freshman year, it s horrible. I can t gain weight, due to the Vyvanse making me lose my appetite and eat much less. I try to force myself to eat as much as possible, but to no avail. At the end of this summer (summer of 2013), I came out of the weight room at 155 lbs, the heaviest I ve ever been. We got into football season, and school started. I began taking vyvanse again, and I lost all my progress. Three hard months of work, gone in 2 months. The vyvanse made me drop weight steadily over those few weeks. I *NEED* to gain weight, and have considered taking weight gain-supplements. During sports, and in the offseason, as I lift and run during both, I take creatine. I would love some help with this, I need to gain weight to maintain my spot on the field (football). I run track, but weight isn t as much of a problem there so much as the lack of energy (lack of appetite). It s also worth noting I do eat a healthy, well-balanced diet.