Hiya I am on 80mg of propanolol and have been for some time (maybe 6 years) originally I was on it for migraine but it wasn't helping then they gave it to me for anxiety. recently I've noticed heart flutters and tightness in my chest -more so than usual so I started monitoring my HR. it got up to 138 today after just doing some washing up etc. and resting at the minute it doesn't go below 80. Could anyone give any advice or have any knowledge why this may be happening whilst on 80mg of propanolol....?