Mcbain, I forgot to mention, if your taking this for adult add/adhd TRY OTHER DRUGS. Ritalin is probably one of the worst for adult add treatment. I have read it many diff places, and I have learned from experience. Talk to your doctor, tell him that ritalin is for children, and to think of something more effective. I recommend you read up on concerta (12 hr release), adderall xr (10 hr release), if you really must, ritalin (sr), or even wellbutrin if your symptoms are chemically induced.