I have had acid reflux all my life. Until I got sick it was not a real problem, just a little annoying once or twice a week, like it is for a lot of people with otherwise average health. But after I got sick it got a lot worse, until it became very bad and I was using over the counter anti-acids several times a day, every day for many years. It was so bad that I even had it in the morning, on an empty stomach.
Eventually I was given a work over by the gastro people who couldn't find anything specific, like Helicobacter infection, etc. But they put me on omeprazole, a strong proton pump inhibitor, and it killed the problem stone cold dead. I can eat & drink anything I want now and it doesn't cause any reflux at all.
If I stop taking it for a couple of days the problem comes right back, as bad as it was before. There are some possible long term side effects of taking the medication for years, but I don't care, life without it is a lot more difficult and unpleasant. There are also some pretty nasty possible consequences of leaving acid reflux untreated too.
Can't tell how wonderful it was to get rid of, or at least properly control, that awful and frequently crippling problem. Wouldn't wish it on anybody.
I think there is a link to ME/CFS.