Omeprazol Dura S (Omeprazole)

Omeprazole is a proton pump inhibitor that addresses conditions caused by excess gastric acid.

• Gastro‑esophageal reflux disease (GERD): provides symptomatic relief and promotes healing of esophageal irritation.
• Erosive esophagitis: accelerates mucosal healing and reduces recurrence of lesions.
• Peptic ulcer disease: supports ulcer healing and prevents recurrence associated with acid hypersecretion.
• Helicobacter pylori eradication (as part of combination therapy): enhances the effectiveness of antibiotic regimens by suppressing gastric acid.
• Zollinger‑Ellison syndrome: controls hypergastrinemia‑driven acid production in this rare endocrine disorder.

• Omeprazole irreversibly binds to the H+/K+‑ATPase enzyme (the gastric proton pump) on the secretory surface of parietal cells. After activation in the acidic canaliculi, it forms a covalent disulfide bond with cysteine residues of the pump, leading to prolonged inhibition of the final step of acid secretion. This markedly reduces basal and stimulated gastric acid output, raising gastric pH and allowing damaged mucosa to heal.

Omeprazole is generally well tolerated, but a range of adverse reactions have been reported.

Common Side Effects

• Headache: mild to moderate intensity.
• Diarrhea: loose stools occurring during treatment.
• Abdominal pain: discomfort or cramping in the stomach area.
• Nausea: feeling of sickness or urge to vomit.
• Flatulence: increased intestinal gas.

Serious or Rare Side Effects

• Clostridioides difficile infection: severe colitis associated with altered gut flora.
• Severe allergic reactions: including rash, angioedema or anaphylaxis.
• Hypomagnesemia: low serum magnesium with prolonged use.
• Bone fractures: increased risk of hip, wrist or vertebral fractures with long‑term therapy.

Before initiating omeprazole therapy, several safety considerations should be reviewed.

• Assess renal and hepatic function: dose adjustment may be needed in severe impairment.
• Use with caution in the elderly: higher incidence of adverse effects.
• Avoid abrupt discontinuation: may cause rebound acid hypersecretion.
• Monitor magnesium levels: especially during long‑term treatment.
• Evaluate for potential infection: prolonged acid suppression can increase risk of gastrointestinal infections.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Omeprazole can affect the pharmacokinetics of several medicines; interactions are classified by clinical significance.

Major Interactions (Avoid)

• Antiretroviral rilpivirine: reduced absorption and efficacy.
• Atazanavir or other protease inhibitors requiring acidic pH: markedly decreased plasma concentrations.
• Ketoconazole and other azole antifungals: impaired absorption leading to therapeutic failure.
• Clopidogrel: decreased conversion to active metabolite, reducing antiplatelet effect.

Moderate Interactions (Monitor Closely)

• Warfarin: possible increase in INR, monitor coagulation.
• Digoxin: modest increase in serum levels, observe for toxicity.
• Methotrexate (low dose): reduced renal clearance, monitor blood counts.
• Phenytoin: may decrease phenytoin levels, adjust dosage as needed.