My long term experience with Metoprolol and Atenolol (similar regular release beta blockers) is my body seems to adjust over time in that my blood pressure returns to normal levels. Still I can have trouble if I make a sudden change in physical activity, say jump to my feet after sitting for more than a few minutes. I have on a few occasions fainted... happily always with a sit down on my part first... or being stabilized by a nearby person. As for fatigue, that can be a side effect for sure. Your does level is quite low in my experience (I take 25 mg twice a day, have taken as much as 100 mg twice a day...ouch, that was trouble big time). Is the beta blocker helping control you AFIb?
Stay with it, and you should adjust. 12mg twice a day is a low dose. By comparison, I'm on 50mg twice a day and dosages or 200mg twice a day aren't uncommon. I believe your body will adjust given a little time.
What about weight gain. I try so hard to lose weight and have been making some progress. Since starting the Metoprolol a few weeks ago I've gained 3.5 lbs. It's hard enough to lose weight having a pill make it tougher or impossible is disheartening.
Have any of you had weight gain? Will the pill continue to put weight on or make it tougher to lose? Or will the gain stop after the intial 3.5 lbs gain?
Metoprolol, like any beta blocker can cause fatigue. You may get used to it, probably will, but there are others that can help your afib that you may not react as badly with. I take atenolol 12.5mg (which is a 25mg tab broken) and I feel tired a lot. However, I have taken this for 30 years! lol
You can try a different beta blocker but for me they all make me tired. You can try the extended release version (XL). You can also switch to a different beta blocker such as CoReg. It didn't work for me, gave me the runs as well as being tired, so I've settled for just napping every afternoon. I'm on 25mg morning and night. Tried upping to 50mg at night but then had to take a morning nap as well so went back 25mg each time. I'm exploring vitamin options as well hoping to eliminate the beta blocker all together or get rid of the napping but no luck so far. Taurine, CoQ10 and L-Carnatine seem to help some with keeping blood pressure in check.