I'm on Vyvanse for about a year now and I've been on thyroid for a long time. I shake and stutter about an hour after I take Vyvanse. When I was new to Vyvanse I lost a bit of weight but my sleepiness and getting cold has come back now despite the Vyvanse and my weight is coming back. I've been told that my thyroid is testing ok but. It seems Vyvanse is pushing my thyroid too hard during the day and is taking away everything the thyroid is supposed to do.