I have been taking Ritalin-SR for about 5 years. The generic version I was getting... was manufactured by Sandoz and had a SZ 780 on the back of the pill. Recently my pharmacist changed my pills but said they are the same as before. New ones are Methlyn ER and have an M on the back. After a month of taking these new pills, I have noticed that they do not have the same effect as the previous ones. Are these the same pills? Should I ask my pharmacist? Perhaps I need to visit another pharmacy and see if they have the same generic pills I was getting before? Thanks!!