"i am a 20 year old female. i have been taking 50mg vyvanse for about 3 months or so. i started taking it during the summer and so my schedule of taking it was rather irregular which caused me to have insomnia and decrease my appetite. i have started school now and it works wonders. i am able to concentrate in class and i have motivation to actually do my homework. i even wish i were in school longer..strange i know. i have experienced the side effects from it, more recently though. i have noticed my heart will race for no real reason, i have become more irritable and on edge (although i&#039;m pretty sure i was like that before), and i tend to get kind of agitated at very minuscule things."