Is it normal for my resting heart rate to sometimes drop to 55? I've been keeping an eye on it using my Apple Watch, and I've noticed this happens on about six days over the past month. I'm currently taking Ciplar LA 20 since July, and before that, I was on Petril Beta for two months. Also, when I exercise, my heart rate shoots up to between 150 and 180 but returns to normal pretty quickly after I stop. I had a stress echo test done last December and everything was fine, but I'm wondering if I need any further testing. What do you think?

Resting heart rate between 54 to 60 beats per minute is considered normal for adults. Since you have a history of taking Ciplar LA 20 and Petril beta, which are beta blockers, it is expected to have a lower resting heart rate. Your heart rate increasing to 150 to 180 beats per minute during exercise is also normal and shows that your heart is responding appropriately to physical activity. As long as your heart rate returns to normal after you stop exercising, and considering your previous normal stress echo test results, there is no immediate need for further testing. Just continue monitoring your heart rate and consult your doctor if you notice any concerning symptoms.