Have you been back to your prescriber since you started on the Vyvanse? I think you will want to share what's going on so he/she can adjust the dose.

I take Vyvanse and have not had any muscle spasms when I do or don't take it. I never feel any effects of Vyvanse during the first hour after I take it. I don't think tolerance builds up quickly on Vyvanse. I have not experienced tolerance and I've been taking it for several years. You just may not have reached what is a therapeutic dose for you yet. It is not unusual for a prescriber to begin at a low dose, monitor symptom response and increase as needed to find what works for you. Reaching the right dose depends on good communication between you and your prescriber--perhaps your office visits will be more frequent until you get the right dose sorted out.