Tonic water can contain up to 83mg/L actual quinine. Three 2L bottles of tonic water could get you 500mg, a therapeutic dose of quinine. Unfortunately, I have not found any place that manufacturers note how much quinine is in their tonic water.
Yeah, I remember reading something similar years ago. But I suspect with the proliferation of "craft tonic water" there may be some "flavours" that don't contain quinine at all.
I read somewhere that gin & tonic was invented because they needed the gin to cover up the taste of the quinine, since the tonic needed to have a _lot_ of quinine to be effective.
As someone who has taken uncoated chloroquine tablets mumble years ago, the taste is one of the most foul bitter over-riding tastes one will ever encounter. No amount of sugar mixed in with it took the edge off the taste. The only thing that did it was when they coated the tablets, preventing the chloroquine from touching the tongue.
I propose a new cocktail consisting of one part gin, three parts tonic, 200 mg hydroxychloroquine plus ice and a slice. Call it a Corona Cocktail maybe. Job done.
