@murphy2370, I completely understand your concern about the long-term effects of Omeprazole, and it's frustrating when you feel caught between difficult choices. Did your doctor say anything to you that there's a rebound effect when stopping PPIs like Omeprazole, especially after 20 years of use?

Or did the doctor simply asked you to stop and start taking famotidine? If so, switching directly from Omeprazole to famotidine after two decades is essentially going cold turkey, which almost guarantees severe rebound hypersecretion. Your stomach had been suppressing acid production for 20 years, and suddenly removing that suppression causes it to overproduce acid temporarily—it can last 2-4 weeks (or even a few months) and can be intense.

Would your GI doctor be willing to work with you on a structured tapering plan? If not, seeking a second opinion might be worthwhile. Your concerns about long-term PPI effects are valid and deserve a more nuanced approach than "take it or risk cancer."

If you do a web search for "how to wean off ppi medication" you'll find some helpful articles on the above.

Best of luck!