It's true that grapefruit cancels out prescription drugs efficacy, though I think most people taking scripts do know this. It's not necessary anyway. Limonene is the active component found in the lemon peel alone. Some people have allergies to it though, hives can occur. A lot of tonic water out there has a lot of added junk ingredients to it including high fructose corn syrup. You can just order pure quinine and put it in some water or juice. You can also order food-grade organic lemon essential oil and put a few drops in 6 oz water or juice. The quinine alone is enough, it's the ability to highly alkalize the tissues is what snuffs out any pathogen that needs an acidic environment to survive and thrive in that makes this effective. I like this one-
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