I too used to eat zantac like candy through the day just to keep the horrible heartburn to a manageable level. I'm talking 2 tablets at a time 3 or 4 times a day. BUT, within a few days of going Primal, the heartburn completely stopped. I believe (for me) it is the wheat that causes it. If I eat something with very much wheat in it these days, I still get heartburn (wheat and sugar together kill me!). But as cavebabymama says, Braggs ACV in some water stops it in it's tracks. I just stay away from wheat now though as it's just not worth it to me.
I wish you luck as I know how miserable this can be!