If you need more than 13 prescribed medicines each year, you could save money with a 12-month PPC. You can also buy a three-month PPC, which will save you money if you need more than three prescribed medicines in three months.
If your GP is willing, you might also be able to get an exemption card for free prescriptions, based on the days you feel at your worst with MS making you unable to get to a chemist. See: