You can get free prescriptions if you are on certain benefits or if you are on a low income. It may be worth contacting Citizens advice bureau to get some advice. You may be entitled to claim PIP but its hard to get it but CAB can help you with the forms for this.

Yes, a PPC (Pre Prescription Certificate) can be purchased online or over the phone, it's a real money saver for anyone who needs continuous/repeat medications. http://www.nhsbsa.nhs.uk/1127.aspx (I hope the link comes out ok)

No I don't I pay for the yearly prepayment certificate i pay just over £100 per year and it covers all prescription costs no matter how many I have in that time. My last prescription cost £80 and that wasn't all of my medications on it x