It seems as if my stomache reacts to ritalin in the morning.. after taking my morning dosage 15mg I always have to use the bathroom..  Its funny, I get a bit agitated in a way, it feels as if i'm nervous.. but i usually dissapears during the morning, but sometimes my stomache is upset during the entrie day.. this could have something to do with that I sometimes take the ritalin before I've had breakfast... lately I've been feeling so tired and lacking energy, I'm a bit worried that because of my upset stomache that my body is unable to get all the nutrients.. but then again it's not as if i have constant diarrhea, it appears to be "yeaterdays news" do I have reason to go see my doctor about this??