Unbearable heartburn

Okay so I'm on my 7th day of Water Fasting and I've had no symptoms whatsoever until the 6th day. And that's just acid reflux/heart burn- it's been pretty unbearable to the point where I think I'm going to vomit. The worst part is it just comes and goes as it pleases, times I'm completely well then others I can't stand it. Anyways what I want to know is there any sort of remedy I could do to help ease the pain without breaking my fast.