Oooh tricky one - I do agree that all life threatening illnesses should be free - but that would be a huge cost. And it would also mean that others that 'need' their medication, but won't die without it would still have to pay - or even pay more.
My mum won't die if she doesn't take her medication - but takes nearly 20 tablets a day for her Parkinson's Disease, Arthritis and High Blood Pressure. Even with the prescription certificate it's still really expensive - and she'll be on most of those tablets for life.