Another name for performance anxiety is stage fright. Stage fright is the fear of performing or doing something in front of a group of people. Performance anxiety, or stage fright, is a subtype of social anxiety disorder, also known as social phobia. Performance anxiety is a only present when you are doing something in front of people, like playing music, competing in sports, singing, or taking a test. Performance anxiety is not present when you are not performing, and it goes away when you finish performing, so the performance anxiety is a discreet and time-limited form of social anxiety disorder. Social anxiety disorder is present all the time, so you are fearful of embarrassing yourself in front of people, while social anxiety disorder- performance anxiety subtype is only present when performing in front of people. In other words, social anxiety disorder is present all the time, while performance anxiety is situationally-based.
These differences do lead to some differences in treatment, as social anxiety disorder responds well with SSRIs (selective serotonin reuptake inhibitors) and SNRIs (serotonin norepinephrine reuptake inhibitors), which is prescribed for daily use. On the other hand, performance anxiety responds well to beta blockers, like propranolol, prescribed only for situations where you have to perform. So if you have performance anxiety, you would take the propranolol one hour before your performance.