Acid blokers reduce the acid in your stomach, and so reduce the uncomfortable symptoms associated with GERD. However the medication actually worsens the underlying problem. Decreased stomach acid can lead to bacterial overgrowth and malabsorption of carbohydrates; and so GERD perpetuates, as does reliance on PPIs.
Acid-blockers can increase the stomach’s pH and worsen the risk of a bacterial infection. Without stomach acid, pathogens can thrive.
When PPIs were first marketed, patients were advised to take them for a maximum of six to eight weeks. But now, it’s not uncommon for patients to be on PPIs for decades.
The parietal cells in your stomach normally release HCl through a proton potassium pump to maintain a very low pH. PPIs inhibit the enzyme required for the pump for up to three days after you take them. When that pump is inhibited, your stomach pH rises as less acid is released.
Histamine H2 receptor antagonists, or H2 blockers, block the histamine receptors in your parietal cells. The cells become less responsive to acid-promoting stimuli, and they release less stomach acid. Though they are less effective than PPIs, H2 blockers like cimetidine, ranitidine, and famotidine still lower stomach acid.
In one study, Tagamet and Zantac, two H2 blockers, raised the stomach pH from 1–2 to 5.5 and 6.5, respectively. PPIs can raise the pH even more. In one study, a 20- or 40-mg dose of Prilosec reduced stomach acid levels to almost zero, and increased the pH to almost 7, in 10 healthy men.
Compared to people on other medications, PPI users have a greater risk of acquiring infectious bacteria like: Clostridium difficile, Campylobacter, Salmonella, Shigella and Listeria. Gastroenteritis, which results in millions of lost work days each year, is also more likely in PPI users. Long-term PPI use also increases the risk of other infections, including: pneumonia, tuberculosis, typhoid and dysentery.
Americans filled over 170 million acid-blocker prescriptions in 2014. When it comes to total cost expenditure, only statins beat out PPIs.