I've recently been prescribed it, too, to go alongside an antidepressant that was causing me more anxiety. Been on Propranolol for about 5 weeks. I haven't had any full-on panic attacks since, and I've really noticed a reduction in the anxiety I've been feeling, and the physical symptoms of that anxiety. Day to day life has been much easier.
I have just had a rough few days because of something that happened, so it's not a total 'cure', but I know I'd have been much worse without the medication, from past experience.
I have been sleeping a lot, so perhaps it is 'knocking me out', but then I tend to sleep a lot because of my depression anyway. It's hard to say. When I am awake though I'm fully alert, not at all drowsy.
It's apparently the drug they prescribe to singers and actors for stage fright. I figured, if it's good enough for them, it's good enough for me! lol.
Meds affect different people in different ways though, so I guess the only thing you can do is try it. Hope it works out for you