I used to be on ritalin. I was taking it for almost 3 yrs. I think it is a great drug for helping you focus, but I also think there are some effects from ritalin that aren't too well known. I would suggest that if you take over 40-50 mg. a day, you should probably get your blood pressure checked on a regular basis. I was up to about 50mg. a day and I started getting really bad headaches, nervousness, really high blood pressure and I ended up having a tachycardia. I have been off ritalin now for about 4 months and have been working out to try to establish a normal blood pressure. Medication effects different people in different ways. I'm not saying what happened to me will happen to everybody. In fact probably .5% of the people taking ritalin will have the effects that I have. Just be careful with what you take and it does sound like you should check your blood pressure on a regular basis. Hope that helped a little. Good luck.