Well, It's been almost a month since I got back on the brand TOPROL XL and I feel like I have my life back. Everyone who has ever experienced PVC's or arrhythmias will tell you that once they start, they ruin your day/week/month. I had a horrible 3 months on the generic Metoprolol Succinate ER. In summary, these were the symptoms that I had, while on the generic.