My heartrate was over 100 resting. They first tested me for thyroid and discovered my thyroid was too high. After takings Levothroid for several months and seeing no difference in my heart rate they decided it was Anxiety causing it and now I'm taking the Thyroid medication in addition to Buspar and Atenolol which is a beta blocker. My heart rate is now less than 100. I'm not sure what the long term side effects of the betablocker are but I know in reading the RX info that it's a drug you can't just stop taking. And I hope to one day get off of it. And as far as the buspar I'm thinking of asking the doctor to try something else. I've been on it over two years and feel it's not working that great anymore.