Is Quinine in Tonic Water Safe?
https://www.peoplespharmacy.com/articles/is-quinine-in-tonic-water-safe
Just a few decades ago, ago you could buy quinine pills over the counter in most pharmacies under brand names like Legatrin, Quinamm and Q-vel.
But the Food and Drug Administration banned the use of OTC quinine to treat leg cramps in 1994. Although this drug has been available for centuries, the FDA has determined that it is far too dangerous to use for anything but malaria.