Can You Take Omeprazole and Vitamin B12 Together?

Long-term omeprazole use can reduce vitamin B12 absorption -- its FDA label documents this directly.

MonitorEvidence: High

What the interaction means

Omeprazole's FDA prescribing information states: "Daily treatment with any acid-suppressing medications over a long period of time (e.g., longer than 3 years) may lead to malabsorption of cyanocobalamin (vitamin B-12) caused by hypo- or achlorhydria." The label recommends considering this diagnosis if B-12-deficiency symptoms appear.

Why it may happen

Stomach acid helps release vitamin B12 from food so it can be absorbed. By suppressing acid production, long-term PPI use can reduce how much B12 the body absorbs.

Practical context

The label frames this as a long-term-use consideration ("longer than 3 years"), not a same-day dosing conflict -- no spacing interval applies. Symptoms of B-12 deficiency should be discussed with a clinician.

What the sources say

Last reviewed 2026-08-22

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.

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