I know this is an old post but I wanted to share this in case it helps someone .. I am 45 years old. I have been taking some type of ADD medication for about 6 years. I work in the software development industry so concentration is a must. I started on Adderall 10MG IR twice a day, for the first few weeks it was fine. Felt a little flighty but not bad. my heart rate on average is about 70-80 while not taking stimulants. On the Adderall 10MG IR, I noticed an hour after taking it my heart rate would jump to the low 90’s. I could feel this but not uncomfortable. It would last for about an hour and a half. The 10MG IR no longer worked so they moved me to 20MG, this worked for concentration but it made my heart rate much worse. An hour after taking it my heart rate would go from 80 to 105-115 and stay there for about three hours. As soon as the Adderall was out of my system it would drop back down to the ’80s. I didn’t like this at all, it made me feel flighty, and just that feeling like I was running a race while sitting at my desk. If I laid on the floor it would go back to about 90 for a few mins. After a few weeks, I noticed palpitations here and there. I didn’t like that at all, sent me to the ER a few times as the palpitations caused a panic attack. Which sucks at 40 as they put you through the Heart test Gauntlet. So I decided to sit with my doctor and try something else, which was both a relief and a disappointment. The disappointment was the fact that Adderall over all Stimulants I have tried works the best for concentration, but had the most side effects. I tried Vyvanse, it was pretty good but I didn’t like the Extended-release. The IR was better for me because some days I may decide I don’t want to take it in the afternoon because of an activity I have etc. once you take an ER you are stuck dealing with it in your system. Finally, I was turned onto 10MG Focalin IR, it has been the stimulant that works well with fewer side effects. Heart rate still goes up but not even close to the Adderall effect. For instance, my resting heart rate today on my apple watch was about 70, I took the Focalin at 7 am and my heart rate is about 85, bounced to the 100’s when walking etc but sitting here typing this it is about 85. Hope this helps someone, it is my individual experience.