H2 blockers are intended to treat unexpected heartburn and lower the amount of acid your stomach produces by blocking the histamine receptors in your stomach that are responsible for triggering acid production. H2 blockers (like PEPCID®) start relieving heartburn symptoms in just 15-30 minutes and control acid for up to 12 hours.
Antacids, like Tums®, are intended to treat unexpected heartburn and neutralize the acid in your stomach, but they don’t block production of more acid. Antacids work quickly, but effects may last up to 2 hours per dose.
Proton Pump Inhibitors (PPIs)
PPIs, like Nexium® and Prilosec®, work by shutting down pumps that release acid into your stomach. PPIs require a 14-day regimen, are intended to treat frequent heartburn, and are not intended for immediate relief. In fact, PPIs may take 1-4 days to fully work*. For consistent heartburn relief you’ll need to keep an even more consistent dosing schedule.