Class: Proton Pump Inhibitor
Dosage Forms. Capsule, Delayed Release: 10 mg, 20 mg, 40 mg; Tablet, Delayed Release: 20 mg; Suspension: 2 mg/mL; Packet: 2.5 mg, 10 mg
Common FDA Label Indication, Dosing, and Titration.
1. Duodenal ulcer disease: 20 mg po daily × up to 4 wk
2. Gastric ulcer disease: 40 mg po daily × up to 8 wk
3. Helicobacter pylori GI infection: 20 mg po bid × 10-14 d in combination with amoxicillin 1000 mg and clarithromycin 500 mg po bid
4. Erosive esophagitis, gastroesophageal reflux disease: Adults and Children 1 y and older and 20 kg or greater, 20 mg po daily; Children 1 y and older, 5-10 kg, 5 mg po daily; Children 1 y and older, 10-20 kg, 10 mg po daily
1. Drug-induced gastrointestinal disturbance, indigestion: 20-40 mg po daily
MOA. Omeprazole is a proton pump inhibitor that, when protonated in the secretory canaliculi of the parietal cells, covalently bind to H+/K+-ATPase (proton pump), which is the final pathway for acid secretion. Produces a profound and prolonged antisecretory effect and inhibits basal, nocturnal, pentagastrin- and food-stimulated gastric acid secretion.
Drug Characteristics: Omeprazole
Medication Safety Issues: Omeprazole
Drug Interactions: Omeprazole
Adverse Reactions: Omeprazole
Efficacy Monitoring Parameters. Resolution of GI discomfort, resolution of ulcers shown on endoscopy; for treatment of H pylori, negative urea breath test.
Toxicity Monitoring Parameters. Severe headache or blistering skin rash. Seek medical attention for signs of liver failure, elevated LFTs.
Key Patient Counseling Points. Should be taken 1 h before meals.
Clinical Pearls. Multiple H pylori regimens exist that include different combinations of PPIs and antibiotics; patients should complete full regimen if prescribed for H pylori management. Many PPI and H2 antagonists available OTC; warn patients not to take multiple products concurrently to avoid additive risk of adverse effects. Increased risk of fractures, especially in elderly. Use lowest effective dose for those at risk for osteoporosis. Medication guide required at dispensing.