I donate platelets at the blood bank. I been doing it for 2 years. This year its been hot (live in arizona). When they check my heart beat, its past 100 and I get defered. One time it was 126 and other times its 102. Last year it was around 88-100. I donated 23 times. My iron level and tempature are good. I sweat easy too. I do get excited sometimes when I go there, I can feel it in my body. I take no medication at all. I drink sports drinks and water before I go. No soda at all. Any advice you can give me to keep my heart beat low? This year has been bad for me. A register nurse (supervisor) who once in awhile does the interview for the donation, said it could be the arizona heat. Any advice will be greatly accepted.