Is that because of lack of money (to see doctor, get prescription, buy drugs) or because of mandatory prescription alone?

Because in civilized countries nobody dies "due to lack of medication" just because a prescription is required.

Except if you mean people can't self-expirement with their own arbitrary self-prescriptions, and die from that because their doctors wouldn't prescribe them the same stuff.

Which is an argument I don't really understand -- is the premise that people informed by the self-study/internet/drug ads/friends/fake news/whatever, know better than a qualified doctor what to prescribe themselves? And that these competent self-prescribers abound so much, that are more in number than the people who would just fuck themselves with BS self-prescriptions?