Peptic ulcer disease (PUD) involves mucosal erosions in the stomach or duodenum resulting from an imbalance between aggressive factors (acid, pepsin, Helicobacter pylori, NSAIDs) and defensive mechanisms (mucus, bicarbonate, prostaglandins). Pharmacological management focuses on acid suppression, H. pylori eradication, mucosal protection, and prevention of recurrence.
What Is Peptic Ulcer Pharmacotherapy?
Treatment goals include symptom relief, ulcer healing, prevention of complications (bleeding, perforation, obstruction), and addressing underlying causes. The recognition of H. pylori infection and NSAID use as the primary etiologies has transformed PUD from a chronic relapsing condition to a curable one.
Drug Classes and Mechanisms
Proton pump inhibitors (PPIs) including omeprazole, pantoprazole, esomeprazole, lansoprazole, and rabeprazole irreversibly inhibit the H+/K+-ATPase pump in parietal cells, producing profound and sustained gastric acid suppression. They are prodrugs activated in the acidic environment of parietal cell canaliculi and provide the most effective acid inhibition of all available agents.
H2-receptor antagonists such as famotidine and nizatidine competitively block histamine H2 receptors on parietal cells, reducing acid secretion by approximately 70 percent. They are less potent than PPIs but have a faster onset of action and are useful for on-demand symptom relief.
Antacids like aluminum hydroxide, magnesium hydroxide, and calcium carbonate neutralize gastric acid, providing rapid symptom relief. They have a short duration of action and limited role in ulcer healing.
Sucralfate forms a protective barrier over ulcerated mucosa by polymerizing in acidic environments. It binds to positively charged proteins in the ulcer base, protecting against acid, bile, and pepsin.
Bismuth subsalicylate has both mucosal protective and antimicrobial effects against H. pylori. It is a component of quadruple eradication therapy.
Misoprostol is a synthetic prostaglandin E1 analogue that stimulates mucus and bicarbonate secretion. It is primarily used for NSAID-induced ulcer prevention, though its use is limited by diarrhea and abortifacient effects.
Therapeutic Uses
Uncomplicated PUD is treated with an eight-week course of a PPI. H. pylori-positive ulcers require eradication therapy: standard triple therapy includes a PPI plus clarithromycin and amoxicillin (or metronidazole in penicillin-allergic patients). Quadruple therapy substitutes clarithromycin with bismuth subsalicylate, metronidazole, and tetracycline, and is used in areas with high clarithromycin resistance or after failed triple therapy. NSAID-related ulcers are managed by discontinuing the offending agent when possible, with a PPI for healing and misoprostol or a PPI for prophylaxis if NSAIDs must continue.
Adverse Effects
PPIs are generally well tolerated but long-term use is associated with potential risks including osteoporosis-related fractures, Clostridioides difficile infection, vitamin B12 deficiency, hypomagnesemia, and community-acquired pneumonia. H2 antagonists may cause headache, confusion in elderly patients, and gynecomastia with high doses of cimetidine due to antiandrogenic effects. Antacids can cause diarrhea (magnesium) or constipation (aluminum). Sucralfate causes constipation and may interfere with absorption of other medications.
Key Clinical Considerations
PPIs should be used at the lowest effective dose and shortest duration necessary. Rebound acid hypersecretion occurs upon abrupt discontinuation after prolonged use, requiring gradual tapering. H. pylori eradication should be confirmed with a urea breath test or stool antigen test at least four weeks after therapy completion. Drug interactions are important: PPIs may reduce clopidogrel activation (controversial) and absorption of vitamin B12 and calcium carbonate.
Conclusion
Peptic ulcer pharmacotherapy has evolved significantly with the advent of PPIs and H. pylori eradication protocols. Identifying and addressing the underlying etiology, whether H. pylori infection or NSAID use, enables effective healing and long-term prevention of recurrence.
