Can citalopram or propranolol cause any sensivity to diary products? i've been taking both the drugs since 2 years ago and it's a year i have bloating

Highly doubtful: I am not aware of any association of those medications with dairy sensitivity. The fact that you took them for a year without the bloating is pretty strong evidence against a link with the medications. Our ability to digest lactose declines after childhood. You are at an age where lactose intolerance can become evident. I suspect that the medications and the bloating are unrelated.