Omeprazol Davur (Omeprazole)

Omeprazole, a proton pump inhibitor, is used to suppress gastric acid production in several gastrointestinal disorders.

• Gastro‑oesophageal reflux disease (GERD): alleviates heartburn and prevents esophageal erosion.
• Erosive oesophagitis: promotes healing of acid‑induced esophageal lesions.
• Peptic ulcer disease: supports ulcer healing and reduces recurrence.
• Helicobacter pylori eradication (as part of combination therapy): enhances the effectiveness of antibiotic regimens.
• Zollinger‑Ellison syndrome: controls excessive gastric acid secretion.

• Omeprazole irreversibly binds to the cysteine‑SH group of the H+/K+‑ATPase enzyme located on the secretory surface of gastric parietal cells. By inhibiting this proton pump, it blocks the final step of acid production, leading to a profound and prolonged reduction of gastric acidity. The effect persists until new enzyme molecules are synthesized, typically 24‑48 hours. The inhibition is dose‑dependent and results in increased gastric pH, which facilitates mucosal healing.

Omeprazole may cause a range of adverse reactions, varying from mild to serious.

Common Side Effects

• Headache: mild, transient headache.
• Diarrhea: loose stools, usually self‑limiting.
• Nausea: mild stomach discomfort.
• Abdominal pain: cramping or discomfort.
• Flatulence: increased intestinal gas.
• Constipation: reduced bowel movements.
• Dry mouth: reduced salivation.

Serious or Rare Side Effects

• Severe allergic reactions: rash, itching, swelling, or anaphylaxis.
• Clostridioides difficile infection: persistent diarrhea with abdominal pain.
• Low magnesium levels (hypomagnesemia): muscle cramps, irregular heartbeat.
• Bone fractures: increased risk with long‑term use.
• Acute interstitial nephritis: kidney inflammation presenting with fever and rash.
• Liver enzyme elevation: abnormal liver function tests.

When prescribing omeprazole, clinicians should consider several safety precautions to minimize risks.

• Assess hepatic function: dose adjustment may be needed in severe liver impairment.
• Monitor magnesium: prolonged therapy can lead to hypomagnesemia; check levels periodically.
• Evaluate for osteoporosis: long‑term use may increase fracture risk, especially in elderly.
• Avoid abrupt discontinuation: tapering may reduce rebound acid hypersecretion.
• Review concomitant medications: potential interactions may require dose modifications.
• Store below 25°C: keep in the original packaging, protect from moisture and light.

Omeprazole can affect the pharmacokinetics of several drugs, leading to clinically relevant interactions.

Major Interactions (Avoid)

• Clopidogrel: reduced antiplatelet activation, increasing cardiovascular risk.
• Atazanavir: decreased absorption, loss of antiviral efficacy.
• HIV protease inhibitors (e.g., ritonavir): reduced plasma concentrations.

Moderate Interactions (Monitor Closely)

• Warfarin: variable INR changes, monitor coagulation.
• Methotrexate: increased serum levels, watch for toxicity.
• Digoxin: altered absorption, check serum levels.
• Phenytoin: decreased clearance, may require dose adjustment.
• Fluconazole: increased omeprazole levels, monitor for side effects.