Confirm allergy history and assess potential interactions (e.g., clopidogrel).
Absolute: hypersensitivity to omeprazole/PPIs. Relative: risk of CDAD, long‑term use concerns (per clinician), interactions via CYP2C19.
Documented hypersensitivity (anaphylaxis, angioedema, severe cutaneous reactions) to omeprazole or other substituted benzimidazole PPIs
Concomitant use with rilpivirine-containing antiretroviral products
Chronic therapy without periodic reassessment—monitor for C. difficile infection and nutrient malabsorption
History of hypomagnesemia, osteoporosis, or long-term diuretic use—check magnesium and bone health during extended courses
Severe hepatic impairment—reduce maintenance doses and monitor liver function
Medications requiring acidic gastric pH for absorption (e.g., atazanavir, ketoconazole, erlotinib)—consider alternatives
High-dose methotrexate therapy—hold omeprazole around chemotherapy to prevent reduced clearance