I took Toprol XL 25 mg for three months after my doc said my BP was really high one day. I experienced horrible side effects---too tired, lethargic, depressed, no desire to do normal tasks, sort of like a walking coma. My BP fell to the 110/65 range. I switched to 12.5 mg for four months, and that's when I developed debilitating BP spikes over 200/110 every month--I had never had a BP spike before in my life. They were caused by the lower dose of Toprol, I believe. Changing to 6.25 mg last week to get off was even worse with the surges, but I felt great and had some energy!!! My doctor put me on Clonidine for the spikes and things are going well. Some Internet posts say that even at tiny doses of Toprol, it can take 3 weeks to get the spikes to stop!! Such a nasty drug! Ask your doc if something else will work for you, and consider Clonidine for that period right after stopping it. After I detox from Toprol, I am not sure I will even need BP medication because it is so low and I am losing weight, eliminating salt, etc. Good luck!