I am not sure where you are, but I am in the USA. We have laws that make employers give time off for medical issues:
U.S. Department of Labor -- ODEP - Office of Disability Employment Policy - Publications - Employment Laws: Medical and Disability-Related Leave

My T has to fill out a form once a year detailing my needs. They include PTSD related breakdowns and time off for therapy during the workday. HR sends it off to the dept of labor and they reply back with a form for the company that says what they need to do to comply with the law. Thankfully I have a great company and they never give me flack.