I am very surprised such a low dose of Toprol causes any side effect... I take 100
mg a day and have taken 100
mg twice a day. At the
200 mg I have some low
BP problems, but they seem to go away after a few days at that level. I take it control my high HR driven by AFib, I wish I could get that down to something like the 60s, I'm usually in the 80s HR. I think 40 is too low, but for some people it, just like low BP, is well tolerated.
Good advice to discuss with your doctor, cardiologist.