Drug interactions
Omeprazole + Vitamin B12
Severity: Minor
Omeprazole and Vitamin B12: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Long-term omeprazole use suppresses gastric acid, reducing release of vitamin B12 from dietary protein. Over months to years this may lower B12 levels, especially in older patients or those with limited intake.
What this interaction means in plain words
Omeprazole and Vitamin B12 have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Omeprazole belongs to Gastrointestinal Tract; Vitamin B12 belongs to Gastrointestinal Tract.
Why it happens
Reduced gastric acid and pepsin activity impairs liberation of protein-bound vitamin B12 for absorption.
What to do
Check serum B12 periodically in patients on long-term omeprazole who have risk factors or symptoms. Supplement if deficiency is confirmed.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Vitamin B12
- Chloramphenicol + Vitamin B12 Moderate
- Dichlorphenamide + Vitamin B12 Moderate
- Metformin + Vitamin B12 Moderate
- Neomycin po + Vitamin B12 Moderate
- Aspirin / citric acid / sodium bicarbonate + Vitamin B12 Minor
- Aspirin + Vitamin B12 Minor
Other interactions of Omeprazole
- Mavacamten + Omeprazole Contraindicated
- Omeprazole + Rilpivirine Contraindicated
- Acalabrutinib + Omeprazole Major
- Atazanavir + Omeprazole Major
- Citalopram + Omeprazole Major
- Clopidogrel + Omeprazole Major
Frequently asked questions
Can I take Omeprazole with Vitamin B12?
MediHelp rates the interaction as minor. Omeprazole and Vitamin B12 have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Long-term omeprazole use suppresses gastric acid, reducing release of vitamin B12 from dietary protein. Over months to years this may lower B12 levels, especially in older patients or those with limited intake.
How serious is the interaction between Omeprazole and Vitamin B12?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check serum B12 periodically in patients on long-term omeprazole who have risk factors or symptoms. Supplement if deficiency is confirmed.
What other medicines interact with Vitamin B12?
MediHelp also lists interactions of Vitamin B12 with, for example, Chloramphenicol, Dichlorphenamide, Metformin. The full list is on the Vitamin B12 page.
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