I was off the 12.5 mg Metoprolol for 6 days and then I started getting a high resting heart rate at night and after a few hours I got anxious and took half a pill and things settled down in less than an hour. I took another half a pill the next night. Now I am skipping this night and will try taking 12.5 mg every other day and see how it goes. I continue taking the Hawthorn tincture and infusion (strong tea) daily. The main side effect with stopping the Metoprolol is an increased resting heart rate and anxiety and sometimes arrhythmia.