I recently read that one of the side effects of taking Advair is rapid heart rate. Please describe to me exactly what that would be (other than having my heart rate checked with a stethoscope), what that would feel like. I have been a 1 time a day user of Advair for about 4 years, 2 weeks ago ran my 1st half marathon. My heart "flutterings", "palpitations" have me rather concerned.