I did a thirty minute cardio work out. Warm up and cool down included, but when I was done, even though my heart rate was normal as well as my breathing my face was bright red and radiating heat. Checked my blood pressure and it was a little high. Couldn't figure out why until I remembered that I took a Zyrtec for my allergies about an hour before hand. Zyrtec has amphetamines. My face is still a little pink, but it's not radiating near as much heat and my bp is coming down. From now on no Zyrtec before working out.