I never had any side effects while taking Novartis's Focalin XR 20 mg. However, now that I'm taking the generic version I'm experiencing dizziness, great difficulty keeping my balance, and lethargy. I also have had some mild headaches. I have only been taking the generic (Sandoz) for a couple of months. I have just turned 68 and have been taking Focalin for a few years. Why is the generic so toxic?