I would think the time-response you describe is very unusual, especially for your relatively low dose of Metoprolol
. I have taken as much as 100 mg
twice a day, time approximate, morning and night, about 12 hours apart. I have also changed to 50 mg twice a day, just started that lower dose this past Sunday.
I take it to lower my HR, and it helps, but I never see anything lower than 70 BPM. It could be lower when I'm asleep, but I have no way of knowing as I'm not on a recording monitor.