How does this stage fright manifest itself?
Lots of people, even famous actors and singers have stage fright.
Taking any prescription medication will need to be reported during a medical and a lot, I mean a lot are not approved for use by pilots.
If this is therapy to help you over teenage shyness I don’t see a problem with it.
If this is a diagnosed fobia we’re looking at something else altogether.
When does talking to a therapist become a problem?
I don’t know, it’s a grey area.
Really only you and your doctor will be able to answer that question.