Medications prescribed for TSC-related manifestations often require a prior authorization (PA). It is important to know what medications will require this, and how long the PA is approved for each medication. For medications that are controlled substances or non-preferred medications, it is common that a new PA cannot be initiated until four days from the last dose covered by the preceding PA. Therefore, it is essential to know exactly what your healthcare team will need to have to initiate the new PA before you run out of mediation. Medications requiring a PA will also be listed on your pharmacy drug list (PDL). Download a Sample Prior Authorization Letter for AMLs or a Sample Prior Authorization Letter for SEGAs.