It's no secret the medical establishment is geared for making money. To 'treat' rather than 'cure'.
Because of that, many of the most effective cures are either not adopted, or are supressed and called superstitious.

Letting people suffer and die to increase your profit margin, it makes me cry.

That is not the only reason for great, effective cures and treatments being largely unknown.
I would like to list any obviously effective cures and treatments here so they are more widely known and can relieve needless suffering.
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Devil's Club http://www.nativeplantsociety.org/devilsclub.htm - Most importantly, it stabilizes blood sugar for diabetics. Overdose on sugar, then drink some devils club, it is astoundingly effective and fast acting. It is not widely known for that purpose because diabetes didnt exist in native culture when medicinal plants were universally used. It also only grows in a limited area (here). Does not keep for more than a year without proper storage. I'll mail you seeds or starter roots, just ask.

Colloidal Silver http://www.soul-guidance.com/health/colloidalsilver.htm - It was never widely used in the past because it was too expensive. Nowdays it is supressed for being too effective for too many things. Though the medical community uses silver for limited things that wont cost them massive amounts of $ in the long run. It kills all single cell organisms. Real colloidal silver looks like tan water, keep out of sun.