Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Proton Pump Inhibitor [EPC], Proton Pump Inhibitors [MoA], Cytochrome P450 2C19 Inhibitors [MoA]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 200329
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Omeprazole is a proton pump inhibitor (PPI) indicated for the: • Treatment of active duodenal ulcer in adults (1.1) • Eradication of Helicobacter pylori to reduce the risk of duodenal ulcer recurrence in adults (1.2) • Treatment of active benign gastric ulcer in adults (1.3) • Treatment of symptomatic gastroesophageal reflux disease (GERD) in patients 2 years of age and older (1.4) • Maintenance of healing of EE due to acid-mediated GERD in patients 2 years of age and older (1.6) • Pathologic hypersecretory conditions in adults (1.7) 1.1 Treatment of Active Duodenal Ulcer Omeprazole delayed-release capsules are indicated for short-term treatment of active duodenal ulcer in adults. Most patients heal within four weeks. Some patients may require an additional four weeks of therapy. 1.2 Helicobacter pylori Eradication to Reduce the Risk of Duodenal Ulcer Recurrence Eradication of H. pylori has been shown to reduce the risk of duodenal ulcer recurrence. Triple Therapy Omeprazole delayed-release capsules in combination with clarithromycin and amoxicillin, are indicated for treatment of patients with H. pylori infection and duodenal ulcer disease (active or up to 1-year history) to eradicate H. pylori in adults. Dual Therapy Omeprazole delayed-release capsules in combination with clarithromycin are indicated for treatment of patients with H. pylori infection and duodenal ulcer disease to eradicate H. pylori in adults. Among patients who fail therapy, omeprazole delayed-release capsules with clarithromycin are more likely to be associated with the development of clarithromycin resistance as compared with triple therapy. In patients who fail therapy, susceptibility testing should be done. If resistance to clarithromycin is demonstrated or susceptibility testing is not possible, alternative antimicrobial therapy should be instituted [see Clinical Pharmacology (12.4) and the clarithromycin prescribing information, Microbiology section]. 1.3 Treatment of Active Benign Gastric Ulcer Omeprazole delayed-release capsules are indicated for short-term treatment (4 to 8 weeks) of active benign gastric ulcer in adults. […]
About this medicine
The active ingredient in omeprazole delayed-release capsules, USP is a substituted benzimidazole, 5-methoxy-2-[[(4-methoxy-3, 5-dimethyl-2-pyridinyl) methyl] sulfinyl]-1H-benzimidazole, a compound that inhibits gastric acid secretion. Its empirical formula is C 17 H 19 N 3 O 3 S, with a molecular weight of 345.42. The structural formula is: Omeprazole USP is a white to off-white powder. Melts between 150°C and 160°C with decomposition. It is soluble in dichloromethane, sparingly soluble in methanol and in alcohol and very slightly soluble in water. Omeprazole USP is supplied as delayed-release capsules for oral administration. Each delayed-release capsule contains either 10 mg, 20 mg or 40 mg of omeprazole in the form of enteric-coated granules with the following inactive ingredients: glyceryl monostearate, hypromellose (5cps), meglumine, methacrylic acid copolymer, poloxamer, sugar globules, talc, titanium dioxide, and triethyl citrate. The capsule shells have the following inactive ingredients: black iron oxide, D & C Red 28, FD & C Blue 1, FD & C Red 40, gelatin, potassium hydroxide, propylene glycol, shellac, titanium dioxide, and yellow iron oxide. Omeprazole delayed-release capsules meets USP Dissolution Test 2. structure
How it works
12.1 Mechanism of Action Omeprazole belongs to a class of antisecretory compounds, the substituted benzimidazoles, that suppress gastric acid secretion by specific inhibition of the H+/K+ ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, omeprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production. This effect is dose-related and leads to inhibition of both basal and stimulated acid secretion irrespective of the stimulus.
Who should not take it
• Omeprazole delayed-release capsules are contraindicated in patients with known hypersensitivity reactions including anaphylaxis to the formulation or any substituted benzimidazole. Hypersensitivity reactions may include anaphylaxis, anaphylactic shock, angioedema, bronchospasm, acute tubulointerstitial nephritis, and urticaria [see Warnings and Precautions ( 5.2 ), Adverse Reactions (6) ]. • Proton pump inhibitors (PPIs), including omeprazole, are contraindicated in patients receiving rilpivirine-containing products [see Drug Interactions (7) ]. • For information about contraindications of antibacterial agents (clarithromycin and amoxicillin) indicated in combination with omeprazole, refer to the CONTRAINDICATIONS section of their package inserts. • Patients with known hypersensitivity to substituted benzimidazoles or any component of the formulation. (4) • Patients receiving rilpivirine-containing products. ( 4 , 7 ) • Refer to the Contraindications section of the prescribing information for clarithromycin and amoxicillin, when administered in combination with omeprazole. (4)
Warnings and cautions
Gastric Malignancy: In adults, symptomatic response does not preclude the presence of gastric malignancy. Consider additional follow-up and diagnostic testing. (5.1) Acute Tubulointerstitial Nephritis: Discontinue treatment and evaluate patients. (5.2) Clostridium difficile-Associated Diarrhea : PPI therapy may be associated with increased risk. (5.3) Bone Fracture: Long-term and multiple daily dose PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. (5.4) Severe Cutaneous Adverse Reactions: Discontinue at the first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation. ( 5.5 ) Cutaneous and Systemic Lupus Erythematosus: Mostly cutaneous; new onset or exacerbation of existing disease; discontinue omeprazole and refer to specialist for evaluation (5.6) Interaction with Clopidogrel: Avoid concomitant use of omeprazole. ( 5.7 , 7 ) Cyanocobalamin (Vitamin B-12) Deficiency: Daily long-term use (e.g., longer than 3 years) may lead to malabsorption or a deficiency of cyanocobalamin. ( 5.8 ) Hypomagnesemia and Mineral Metabolism: Reported rarely with prolonged treatment with PPIs. (5.9) Interaction with St. John’s Wort or Rifampin: Avoid concomitant use of omeprazole. ( 5.10 , 7 ) Interactions with Diagnostic Investigations for Neuroendocrine Tumors: Increased Chromogranin A (CgA) levels may interfere with diagnostic investigations for neuroendocrine tumors; temporarily stop omeprazole at least 14 days before assessing CgA levels. ( 5.11 , 7 ) Interaction with Methotrexate: Concomitant use with PPIs may elevate and/or prolong serum concentrations of methotrexate and/or its metabolite, possibly leading to toxicity. With high dose methotrexate administration, consider a temporary withdrawal of omeprazole ( 5.12 , 7 ). Fundic Gland Polyps: Risk increases with long-term use, especially beyond one year. Use the shortest duration of therapy. ( 5.13 ) 5.1 Presence of Gastric Malignancy In adults, symptomatic response to therapy with omeprazole does not preclude the presence of gastric malignancy. […]
Reported side effects
The following serious adverse reactions are described below and elsewhere in labeling: • Acute Tubulointerstitial Nephritis [see Warnings and Precautions (5.2) ] • Clostridium difficile -Associated Diarrhea [see Warnings and Precautions (5.3) ] • Bone Fracture [see Warnings and Precautions (5.4) ] • Cutaneous and Systemic Lupus Erythematosus [see Warnings and Precautions (5.6) ] • Cyanocobalamin (Vitamin B-12) Deficiency [see Warnings and Precautions (5.8) ] • Hypomagnesemia and Mineral Metabolism [see Warnings and Precautions (5.9) ] • Fundic Gland Polyps [seeWarnings and Precautions (5.13) ] Adults: Most common adverse reactions in adults (incidence ≥2%) are • Headache, abdominal pain, nausea, diarrhea, vomiting, and flatulence (6) Pediatric patients (2 to 16 years of age): • Safety profile similar to that in adults, except that respiratory system events and fever were the most frequently reported reactions in pediatric studies. (8.4) To report SUSPECTED ADVERSE REACTIONS, contact Dr. Reddy’s Laboratories Inc., at 1-888-375-3784 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience with Omeprazole Monotherapy Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety data described below reflects exposure to omeprazole delayed-release capsules in 3096 patients from worldwide clinical trials (465 patients from U.S. studies and 2,631 patients from international studies). Indications clinically studied in U.S. trials included duodenal ulcer, resistant ulcer, and Zollinger-Ellison syndrome. The international clinical trials were double blind and open-label in design. The most common adverse reactions reported (i.e., with an incidence rate ≥2%) from omeprazole-treated patients enrolled in these studies included headache (7%), abdominal pain (5%), nausea (4%), diarrhea (4%), vomiting (3%), and flatulence (3%). […]
Interactions with other medicines
Tables 3 and 4 include drugs with clinically important drug interactions and interaction with diagnostics when administered concomitantly with omeprazole and instructions for preventing or managing them. Consult the labeling of concomitantly used drugs to obtain further information about interactions with PPIs. Table 3: Clinically Relevant Interactions Affecting Drugs Co-Administered with Omeprazole and Interaction with Diagnostics Antiretrovirals Clinical Impact: The effect of PPIs on antiretroviral drugs is variable. The clinical importance and the mechanisms behind these interactions are not always known. • Decreased exposure of some antiretroviral drugs (e.g., rilpivirine, atazanavir and nelfinavir) when used concomitantly with omeprazole may reduce antiviral effect and promote the development of drug resistance [see Clinical Pharmacology (12.3) ]. • Increased exposure of other antiretroviral drugs (e.g., saquinavir) when used concomitantly with omeprazole may increase toxicity [see Clinical Pharmacology (12.3) ]. • There are other antiretroviral drugs which do not result in clinically relevant interactions with omeprazole. Intervention: Rilpivirine-containing products: Concomitant use with omeprazole is contraindicated [see Contraindications (4) ]. Atazanavir: Avoid concomitant use with omeprazole. See prescribing information for atazanavir for dosing information. Nelfinavir: Avoid concomitant use with omeprazole. See prescribing information for nelfinavir. Saquinavir: See the prescribing information for saquinavir for monitoring of potential saquinavir-related toxicities. Other antiretrovirals: See prescribing information for specific antiretroviral drugs. Warfarin Clinical Impact: Increased INR and prothrombin time in patients receiving PPIs, including omeprazole, and warfarin concomitantly. Increases in INR and prothrombin time may lead to abnormal bleeding and even death. Intervention: Monitor INR and prothrombin time and adjust the dose of warfarin, if needed, to maintain target INR range. […]
Use in specific groups
8.1 Pregnancy Risk Summary There are no adequate and well-controlled studies with omeprazole in pregnant women. Available epidemiologic data fail to demonstrate an increased risk of major congenital malformations or other adverse pregnancy outcomes with first trimester omeprazole use. Reproduction studies in rats and rabbits resulted in dose-dependent embryo-lethality at omeprazole doses that were approximately 3.4 to 34 times an oral human dose of 40 mg (based on a body surface area for a 60 kg person). Teratogenicity was not observed in animal reproduction studies with administration of oral esomeprazole (an enantiomer of omeprazole) magnesium in rats and rabbits during organogenesis with doses about 68 times and 42 times, respectively, an oral human dose of 40 mg esomeprazole or 40 mg omeprazole (based on body surface area for a 60 kg person). Changes in bone morphology were observed in offspring of rats dosed through most of pregnancy and lactation at doses equal to or greater than approximately 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age [ see Data ]. The estimated background risks of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data Four published epidemiological studies compared the frequency of congenital abnormalities among infants born to women who used omeprazole during pregnancy with the frequency of abnormalities among infants of women exposed to H 2 -receptor antagonists or other controls. […]
If too much is taken
Reports have been received of overdosage with omeprazole in humans. Doses ranged up to 2400 mg (120 times the usual recommended clinical dose). Manifestations were variable, but included confusion, drowsiness, blurred vision, tachycardia, nausea, vomiting, diaphoresis, flushing, headache, dry mouth, and other adverse reactions similar to those seen in normal clinical experience [see Adverse Reactions (6) ]. Symptoms were transient, and no serious clinical outcome has been reported when omeprazole was taken alone. No specific antidote for omeprazole overdosage is known. Omeprazole is extensively protein bound and is, therefore, not readily dialyzable. In the event of overdosage, treatment should be symptomatic and supportive. If over-exposure occurs, call your Poison Control Center at 1-800-222-1222 for current information on the management of poisoning or overdosage.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 17 July 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.