Yeah, I seemed to have gotten more sensetive as well to caffeine/ephedrine products lately. I get the flushing in the face and ears sometimes as well. I've been taking eca off and on for years. Lately I've noticed that when I take ephedrine, I develop heart palpitations, where it feels like your heart skips a beat and then there is an extra strong beat a second later. It's weird and kinda freaked me out, and from what I've read it's normally ok, and is due to caffeine, ephedrine, or nicotine or sometimes even alcohol. So I'm seriously going to try to cut back on the stimulants for a while. One thing that I like that does give me energy is cayanne. The capsules are pretty cheap at GNC or usually anywhere, and they have a nice stimulating affect, it just doesn't last long. They just take some getting used to because they can clean you out pretty good at first.lol I also used to use them when I boxed because cayanne besides being a powerful antioxidant also helps blood coagulate faster.