I started taking ritalin about 1 1/2 years ago for idiopathic hypersomnia. I take 10 mg 3 times a day. I take it a 7am noon, and 3pm. when I first started taking it I noticed that it would knock the shadows down fairly quick. After a few months it lost its effect on them. I have never tried to abort an attack with it. I have thought about it but decided to stick to my schedule, if it worked it I would be to easy to start abusing.