I'm glad a drug like this exists because it can be so uncomfortable when you produce too much stomach acid.
When I went traveling in a malaria prone country, when I returned the doctor gave me some pills to clear the malaria out of my system (if I had any). The instructions for taking the pills wasn't very clear and I ended up taking two at once each day, instead of taking them separately in the morning and night.
It really made my stomach acid go nuts and it ended up burning the sphincter that connects the end of the throat with the stomach. So, every time I swallowed, it hurt. And that was just a little bit of overproduction. I don't want to imagine what it feels like for someone who's got cancer or something on top of it.