1. Proton Pump Inhibitors (PPI’s), with generic names ending “-azole.” These include omeprazole (Prilosec®), pantoprazole (Protonix®), Lansoprazole (Prevacid®), esomeprazole (Nexium®), & others.
2. Histamine-2 Receptor Blockers (H2RB’s), with generic names ending “-tidine.” They include famotidine (Pepcid®), ranitidine (Zantac®), cimetidine (Tagamet®) and nizatidine (Axid®).
3. Combination products with both Aluminum hydroxide plus Magnesium hydroxide. Brand names include Maalox® and Mylanta®, although cheaper generic versions are sold everywhere.
The PPI’s are the strongest. If we try a “therapeutic trial” to diagnose stomach disease (which could be any of the conditions mentioned), it’s best to use high doses of a PPI. If we use lower doses, or weaker drugs, and symptoms don’t improve, we won’t know if it’s not the stomach, or we simply didn’t give strong-enough medication. But we have minor concerns about using long-term, high-dose PPI’s, like possible osteoporosis (bone loss), or increased risk of gastrointestinal infections (since we’ve wiped out the protective acid). Also, they may mask the pain of stomach cancer (see below). So we try to lower the dose, or switch to a milder drug for ongoing use.
H2RB’s often work just fine for any of the mentioned stomach conditions. We’re not concerned about long-term use. Also, these won’t mask the pain of stomach cancer the way PPI’s might. This means if you have pain from stomach cancer, it might improve on a PPI, so the diagnosis gets missed. The pain wouldn’t be relieved by H2RBs.
Aluminum + Magnesium antacids are the oldest of these drugs, often marketed as white liquids. They work as well as the others; before the first H2RB (cimetidine) was invented in the early 1980’s, we could cure an ulcer with liquid antacids taken every 2 hours while awake. But who wants to have to do that? The advantage of liquid antacids is that they work quickly, and can be taken as-needed for people who don’t require daily pills.