Hello I Am Extremely Concerned About This Medication...my Son Came

hello i am extremely concerned about this medication...my son came home from school asking me what Vyvanse was and that a bunch of kids were taking it and one got caught...how are they acquiring this and how serious can this be if taken recreationally...i am a concerned parent and would like to know what signs to look for if my son so much as gives in to peer pressure..i want to be on top of this...