Man I seem to really get the cruddy end of the stick when it comes to a lot of meds....I have an extremely high metabolism and I'm hypersensitive to everything I take. a can of coca-cola will give me a jolt for about an hour and a half. If there's a side effect to a med, I seem to get it...especially the negative ones. Lucky me eh? I'm glad it's at least helping some people out there but I really wish my doctor who was freaking aware of my insomnia issues already would have advised me about these possible side effects before telling me to take it. Just goes to show ya that even though your doctor says a med is safe, you should always do your own research before taking that first pill.