Hi CC
I've had this at times in the past. I have a prescription for stuff called Ranitidine, which is a bit stronger than over-the-counter stuff like Zantac (never sure how these names translate between UK and US). I don't have to take these all the time, just when it strikes. Nowadays I tend to pop a pill when I feel it coming on, rather than wait until it gets really bad... and it can get really bad!
The big question is why is it happening. I find it can be related to what I've eaten, but I'm much more careful about what I eat now, so it rarely happens.
However, I've also found it can be set off by stress... that usually means work-related. I've got much less control over that than I have over my diet, but I always keep the pills with me.
Hope that helps