AFEB after taking Metoprolol

Hi, I am an AF patient. It is not likely that metoprolol would induce AF, but it is possible your heart rate went too low on it and you experienced some of the symptoms of bradycardia (officially a heart rate lower than 60 BPM, although athletes like us routinely run in the low 40's, even lower at times). But, if whatever heart rate it was was too low for YOU, then you'd feel unwell. Then, when your rate zoomed up to 100, it was an adrenalin response because your system sensed you were in danger. That would also make you sweat.
I had to be taken off metoprolol urgently because it was putting me at grave risk with a heart rate near 30 when my heart wanted to play nice, and the nurse in the ICU said I had pauses that long (holding her forefingers about 6 inches apart) on their nurses' station display of my telemetry.
You should let your physician/cardiologist know of these events, especially if they repeat.

I also experienced fatigue and lightheadedness after taking Metoprolol for Afib. 50mg /day. As an active person, it felt like a head-wind that I had to push through whenever I exerted myself. I'm guessing it may be because the drug limits the force of the heart's contractions, and as a result, the body is not receiving the oxygen-rich blood as efficiently as it needs during strenuous activity? But I'm just guessing.

I was on metoprolol for about 6 months. Both before and after a successful ablation that so far has kept me out of Afib. I did not like the effects of metoprolol from the very beginning. At times my heart rate was in the low 50s and never got into the high 60s even with moderate exercise. I am no longer an athlete, so this is really low for me. It made me sluggish, and I was kind of wobbly when I walked. My legs from the knees down felt like they were just along for the ride. They felt very heavy. Since I stopped metoprolol about 4 or 5 weeks ago, I feel 100% better. My heart rate now is +/- mid 60s when resting and +/- mid 70s with moderate exercise. Sometimes in the low 80s if I am really working hard for long periods. Sitting at my computer right now my heart rate according to my Cardio Mobile is 63 and normal sinus rhythm.

I also take Metropolol 25gms morning and night. Never had problems until the Cardiologist took me off them and straight away I went in to AF. So once back on I was fine. What was happening to me me is I'd get extremely breathless and have to lie down for 15mins. I was extremely tired and got sweats at night. I had an ablation and Pacemaker installed. I still go in to AF but my heart rate doesn't go past 100 whereas my heart rate was at times 220.