Personally, I find that taking them as and when I think I need them is enough - for example, I might take a dose half an hour before setting off on a shopping trip, making a phone call, socialising etc. They act in about 1/2 to one hour, and the calming effect seems to last for an hour or two. I don't find the need to take them every day, and there's no waiting around for weeks to see what effect they have, as would be common for anti-depressants.
The only side effects I've noticed are a slightly dry mouth, and some postural hypotension (dizzy spells if I stand up too fast, due to lowered blood pressure.) You should, of course, check with your GP first, as there are certain medical conditions and other medications which could interact badly (for example, if you are already on medication for high blood pressure or have a heart condition.)
As a Brit, I can't advise on the cost, though I do know that the one I take, propranolol, is now out of patent, so there are generic versions which may be cheaper than branded ones.
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