You only need a little. It doesn't taste too good, but it gets the job done! For major cramps try half centimetre in a glass, for minor cramps, try four two spoons. If your going for a long exercising period, bring a small flask of it with you! Once you have a quick sit, the cramp should go away within ten seconds. It really helps!
This is a real thing, and I'm not just making it up!