Vodka. Tonic water. Two horrible-tasting things that, combined, aren't all that bad. Sort of like sodium and chlorine. Anyway, it'll take you a couple of these to set you on your feet again.
Sodium, a dangerously reactive metal, and chlorine, a toxic gas, "combine" to form sodium chloride, more commonly known as salt.
The item description is a reference to the Elton John song, Goodbye Yellow Brick Road, which says, "It'll take you a couple of vodka and tonics to set you on your feet again."