Omeprazol Laboratórios Azevedos (Omeprazole Sodium)

Omeprazole is a proton pump inhibitor that acts on the gastric acid secretion pathway. It is indicated for several acid‑related disorders:

• Gastro‑oesophageal reflux disease (GERD): provides relief of heartburn and promotes healing of erosive esophagitis.
• Peptic ulcer disease: supports ulcer healing and reduces risk of recurrence.
• Zollinger‑Ellison syndrome: controls excessive gastric acid secretion associated with gastrin‑producing tumors.
• Helicobacter pylori eradication regimens: used as part of combination therapy to improve eradication rates.
• NSAID‑associated ulcer prevention: lowers the risk of ulcer formation in patients requiring long‑term non‑steroidal anti‑inflammatory drug therapy.

• Omeprazole selectively and irreversibly binds to the H+/K+‑ATPase enzyme (the gastric proton pump) on the secretory surface of parietal cells. By inhibiting this final step of acid production, it markedly reduces both basal and stimulated gastric acidity, allowing the gastrointestinal mucosa to heal and decreasing reflux of acid into the esophagus.

Omeprazole is generally well tolerated, but adverse reactions can occur.

Common Side Effects

• Headache: mild to moderate intensity.
• Diarrhoea: usually transient.
• Nausea or abdominal discomfort: occasional.
• Flatulence: mild bloating.
• Constipation: infrequent.
• Dry mouth: occasional.

Serious or Rare Side Effects

• Clostridioides difficile infection: severe colitis risk.
• Acute interstitial nephritis: renal inflammation.
• Hypomagnesemia: low serum magnesium levels.
• Osteoporotic fractures: increased risk with long‑term use.
• Severe cutaneous adverse reactions: such as Stevens‑Johnson syndrome.
• Anaphylaxis: rare systemic allergic reaction.

Omeprazole should be used with consideration of patient‑specific factors and proper handling.

• Assess renal and hepatic function: adjust use if impairment is present.
• Review concomitant medications: potential for altered absorption or interaction.
• Limit duration of therapy: avoid unnecessary long‑term use.
• Monitor for vitamin B12 deficiency: especially with prolonged treatment.
• Counsel on potential rebound acid hypersecretion after discontinuation.
• Store at below 25°C: keep in the original packaging, protect from moisture and direct sunlight.

Omeprazole may affect the pharmacokinetics of several co‑administered drugs.

Major Interactions (Avoid)

• Clopidogrel: reduced antiplatelet effect, may increase cardiovascular risk.
• Atazanavir and other protease inhibitors: decreased absorption, loss of antiviral efficacy.

Moderate Interactions (Monitor Closely)

• Warfarin: possible increase in INR, monitor coagulation parameters.
• Methotrexate: reduced renal clearance, watch for toxicity.
• Digoxin: increased serum concentrations, assess cardiac status.
• Diazepam: elevated levels may cause sedation, adjust dose if needed.
• Iron supplements: reduced absorption, separate dosing times.