Heather,
Yes, beta-blockers make weight control tough...BUT you can always eat less to compensate for the lowered metabolic rate.
Yes, a lower dose of beta blocker will have less of a weight gaining effect but also less of ALL effects. Why not try 25 mg. metopolol twice a day. You don't want to take metoprolol LESS than twice a day because it is so short acting.
Maybe the 25 x 2 will still give you most of the benefits with less of the grief (fatigue and weight stasis.)
Since you are getting THREE benefits from the metoprolol, tachy and PVC and anxiety control, it sounds like a drug you might want to continue with.
I hope the 25 X 2 regimen works for you. Give it a MONTH though before you judge its effects. The first several weeks are apt to be tough sledding after 3 years on the higher dosage...you might feel jumpy, anxious and prone to some tachcardia. Check your BP regualrly so you don't see any 180 systolics.
(IF you tell your doctor, he will try to talk you out of it...your call!

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