Acid suppression therapy (PPIs, H2 blockers, antacids)
Acid suppression therapy spans proton pump inhibitors (PPIs), histamine-2 receptor antagonists (H2RAs), and antacids, used to treat and prevent reflux, peptic ulcer disease, and bleeding. A once-daily PPI, such as omeprazole 20 mg before breakfast, is first-line for most indications; H2RAs and antacids serve milder or adjunctive roles.
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What this article covers
- Overview
Acid suppression therapy is the group of drugs that reduce or neutralize gastric acid: proton pump inhibitors (PPIs), histamine-2 receptor antagonists (H2RAs), and antacids, with sucralfate and misoprostol as adjuncts.
- Epidemiology
Broad indication base: Gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD), Helicobacter pylori eradication, nonsteroidal anti-inflammatory drug (NSAID) ulcer prevention…
- Risk factors
Older age: Greater susceptibility to PPI-associated fracture, H2RA-related confusion, and reduced drug clearance.
- Pathophysiology
Proton pump inhibitors: Prodrugs activated in the acidic parietal-cell canaliculus, then irreversibly and covalently bound to the H+/K+-ATPase; activation needs active acid secretion, so pre-meal…
- Clinical features
PPI, common effects: Headache, diarrhea, dyspepsia.
- Differential diagnosis
PPI versus H2RA for GERD: A PPI heals erosive esophagitis, but an H2RA is chosen instead for mild, short nonerosive symptoms or nocturnal breakthrough, since it does not require pre-meal timing.
- Diagnosis
What establishes the need for acid suppression: GERD is diagnosed clinically from typical heartburn or regurgitation without alarm features, supporting an empiric PPI trial; PUD is most often…
- Management
First-line, most indications: Start a PPI once daily, 30 to 60 minutes before breakfast: omeprazole 20 mg PO daily for GERD relief and erosive esophagitis healing, for 8 weeks before reassessment.
- Complications
Hypomagnesemia: Sustained PPI use, presenting as tremor, arrhythmia, or seizure, worse with concurrent diuretics.
- Prognosis
GERD healing: Most patients heal erosive esophagitis within an 8-week PPI course; escalated twice-daily dosing controls most remaining partial responders.
- Prevention
Screen before prescribing NSAIDs long-term: Age over 65 or a prior ulcer or bleed pairs the NSAID with a PPI, or misoprostol if PPI-intolerant.
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Related articles
- Gastroesophageal reflux disease (GERD)
GERD is retrograde reflux of gastric contents into the esophagus causing heartburn and regurgitation, diagnosed clinically and confirmed by response to an empiric PPI trial, with endoscopy reserved for alarm features or refractory symptoms. Management proceeds from lifestyle measures through an 8-week once-daily PPI trial, dose escalation or agent switch for partial response, and fundoplication for medication-refractory or regurgitation-predominant disease.
- Peptic ulcer disease
Peptic ulcer disease is a mucosal break in the stomach or duodenum caused chiefly by Helicobacter pylori infection or NSAID use, diagnosed by upper endoscopy with biopsy of gastric ulcers to exclude malignancy. Treatment eradicates H. pylori when present, stops the ulcerogenic drug, and heals the ulcer with a proton pump inhibitor, while its complications of bleeding, perforation, and obstruction drive most of its morbidity.
- Barrett esophagus
Barrett esophagus is metaplasia of the distal esophageal squamous lining into intestinal columnar epithelium driven by chronic GERD, and it is the established precursor of esophageal adenocarcinoma. Diagnosis requires endoscopy showing salmon-colored mucosa above the gastroesophageal junction confirmed by biopsy showing intestinal metaplasia with goblet cells, and management, from surveillance interval to endoscopic ablation, is dictated entirely by the graded dysplasia.
- Dyspepsia
Dyspepsia is chronic or recurrent epigastric pain, burning, postprandial fullness, or early satiety that is organic when a structural, metabolic, or drug cause is found and functional when Rome IV criteria are met after a negative workup. Management starts with an alarm-feature screen that mandates prompt upper endoscopy, then test-and-treat for Helicobacter pylori, then an empiric proton pump inhibitor trial, reserving a tricyclic or prokinetic agent for confirmed functional disease.
- Acute upper gastrointestinal bleeding
Acute upper gastrointestinal bleeding arises proximal to the ligament of Treitz and presents with hematemesis or melena, most often from peptic ulcer disease or bleeding gastroesophageal varices. Management sequences resuscitation, restrictive transfusion, IV proton pump inhibitor therapy, and, when varices are suspected, octreotide plus antibiotic prophylaxis, all before upper endoscopy within 24 hours, which is both diagnostic and therapeutic.
- Nonsteroidal anti-inflammatory drugs
Nonsteroidal anti-inflammatory drugs (NSAIDs) relieve pain, fever, and inflammation by inhibiting cyclooxygenase (COX)-1 and COX-2, and that single mechanism predicts every major toxicity: gastric ulceration, platelet dysfunction, and hemodynamic renal injury. First-line agents are naproxen or ibuprofen (or topical diclofenac for knee or hand osteoarthritis) at the lowest effective dose for the shortest duration, with a proton pump inhibitor such as omeprazole 20 mg once daily added for patients at increased gastrointestinal risk.
- Gastrinoma (Zollinger-Ellison syndrome)
Gastrinoma is a gastrin-secreting neuroendocrine tumor, usually arising in the duodenum or pancreas, that drives the acid hypersecretion of Zollinger-Ellison syndrome: recurrent, multiple, or refractory peptic ulcers plus diarrhea. Diagnosis rests on a markedly elevated fasting serum gastrin with a low gastric pH, then imaging to localize the tumor. First-line treatment is high-dose proton pump inhibitor therapy, with surgical resection when disease is not metastatic.