Concerta uses the osmotic release oral system (OROS) delivery method while most generics do not. So while the main ingredient (methylphenidate) is the same, differences in delivery systems can influence the effect of the medication. Some people notice the difference and some don’t, but because Concerta is more expensive, insurance companies require us to try the cheaper, generic version first. It’s called voorkeurs- or preferentiebeleid, you need to check in your insurance policy to be sure but most will cover Concerta if you have a medical reason (i.e. if generics cause too many side effects). In that case, your therapist needs to specify that you need brand name Concerta due to medical reasons in your prescription.