You have a difficult decision to make, given that it is an internship. If you are being paid and there are a x number of employees they may have to give you your request based on the family leave act, which includes dentist, doctor, parent-teacher conferences, etc to take care of business. You would have to look up the exact regulations. You can use the term medical appointment and they cannot ask for the specifics. As an intern, I would not use this bite the bullet and take the time away from therapy, find a temporary therapist, or Skype/phone my current therapist. There is just to much at stake.Not everyone in an organization is tolerant about time off for whatever the reasons maybe.