"It contains a mixture of magic and medicine with invocations to banish disease and a catalogue of useful plants, minerals, magic amulets and spells."

So it doesn't, except when it does.

I'd also argue a lot of medicine employed 'magical thinking' such as efficacy from similarity. Herbs were recommended based on their physical similarity to organs or parts of the body. I don't think it's pejorative of early practitioners to point this out. Until empiricism and experimentalism there was no way to reliably clarify what worked and why.