I am a 40 year old, non smoking, non drinking, no caffein intaking female with asthma. I recently had a stress/echo due to multiple PVC's per day. The test showed that my heart lining has thickened due to undiagnosed high BP (the doc thinks I have sleep apnea which is causing a rise in bp at night, without my knowing). The doc put me on Toprol 25mg...could NOT breath. He has now changed me to Cartia XP 240mg...I can now breath fine, but my heart beats seems very, very hard, not fast (85 bpm), just very hard. When I try to lie down, they keep me awake, they are so hard. Is this normal with this medication?? The PVC have dramatically slowed, maybe one or two a day, but I seem to have a headach I can't seem to get rid of.