Funny you should ask... I just got back from a gastro. appt. right now to discuss this very thing.
My gastro. doc told me that it is safe to take antacids for an extended period. There have been studies showing that after 10-15 years in VERY high doses, they can lead to a certain form of RARE cancer, but these studies have ONLY been found in mice (of course) and not humans since we don't take such high doses. Therefore, he said the benefits outweigh any (if there are any) risks. He said if you don't take them and your acid backs up into your esophagus it can lead (more likely than taking too much antacid) to cancer as well, so it is best to keep it at bay.
I have heard many CFers have troubles with reflux due to our messed up digestive systems, so it is completely normal to be on antacids indeffinately. I've also heard that for CFers not to be on antacids, it can be dangerous and even lead to worsening of the lungs if not treated due to ruining our esophogus and making it harder to breathe.
I've been on Prilosec for about 7 months and today got put on Aciphex for a change to see if it works better. I get heartburn with water too! I will stay on antacids as long as the give me relief. No worries.
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