When starting all beta blockers, they seem to make you a little more tired than usual. This can effect memory a little bit. Sometimes though, concentration seems to improve. I also find I sleep less than usual which can also effect memory. As your body adjusts to the medication the sleep problems seem to improve. Bystolic is great compared to other beta blockers in terms of energy levels. Other beta blockers including Toprol XL made me definitely feel more sluggish and lazy.