HI..THANKS for writing.. you are having situational anxiety more precisely called as performance anxiety..for taht you shud take beta blocker like propranolol, you shud not take bisoprolol because it is not approved for anxiety and it self it can cause anxiety because it is centrally acting drugs..it has not been well tested for its effects on anxiety.. if you have social shyness that is what it is called then consult a psychiatrist or counsellor, go for sessions and for situations like social gatherings you can take propranolol as and when required basis... i hope this will be helpful..best of luck..