NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated August 1, 2026

Supplement × Prescription·Evidence index

Iron and Omeprazole: what the published research says

PubMed indexes 8 records that name Iron and Omeprazole together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.

Read this first

An evidence index, not guidance.

Every statement below is attributed to a named, dated, linked source.

This page lists published research relevant to Iron and Omeprazole. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.

The research

8 studies naming Iron and Omeprazole.

Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.

Effect of omeprazole on oral iron replacement in patients with iron deficiency anemia.

Southern medical journal · 2004 · PMID 15455980

Case ReportsHuman subjects

“Our observations support the probability that the profound hypochlorhydria induced by omeprazole may indeed impair the optimal absorption of orally administered iron in iron-deficient individuals, precluding them from obtaining therapeutically adequate amounts to establish the positive balance necessary for the resolution of anemia and the replenishment of stores. The possible explanations for this phenomenon are also discussed.”

Sharma et al. · From the abstract

Names both Iron and Omeprazole in its title.

Effects of omeprazole on iron absorption: preliminary study.

Turkish journal of haematology : official journal of Turkish Society of Haematology · 2013 · PMID 24385811

“Administration of omeprazole for a short duration does not affect absorption of orally administered iron in healthy individuals.”

Tempel et al. · Authors' conclusion

Names both Iron and Omeprazole in its title.

Suboptimal response to ferrous sulfate in iron-deficient patients taking omeprazole.

American journal of therapeutics · 2012 · PMID 21150767

Human subjects

“Omeprazole and possibly all proton pump inhibitors decrease the absorption of oral iron supplementation. Iron-deficient patients taking proton pump inhibitors may have to be treated with high dose iron therapy for a longer duration or with intravenous iron therapy.”

Ajmera et al. · From the abstract

Names both Iron and Omeprazole in its title.

Serum iron, ferritin, and vitamin B12 during prolonged omeprazole therapy.

Journal of clinical gastroenterology · 1992 · PMID 1607604

Human subjects

“Serum vitamin B12 and folic acid levels were normal in all cases. We conclude that iron, vitamin B12, and folic acid malabsorption is unlikely to occur, at least within the initial 3-4 years of continuous omeprazole therapy.”

Koop et al. · From the abstract

Names both Iron and Omeprazole in its title.

Inhibition of iron absorption by omeprazole in rat model.

Digestive diseases and sciences · 1991 · PMID 2007356

Animal study

“There was no significant reduction in the absorption of ferric iron. Omeprazole therapy is unlikely to be associated with significant iron malabsorption in normal patients but may reduce iron absorption in pathological states associated with increased iron absorption such as iron deficiency.”

Golubov et al. · From the abstract

Names both Iron and Omeprazole in its title.

Medication and supplement pharmacokinetic changes following bariatric surgery: A systematic review and meta-analysis.

Obesity reviews : an official journal of the International Association for the Study of Obesity · 2024 · PMID 38710656

Systematic ReviewMeta-AnalysisHuman subjects1985 participants

“This study demonstrates heterogeneity in practice and could not reach conclusive findings for most PK parameters. Prospective studies are needed to inform best practice and enhance patient healthcare and safety following bariatric surgery.”

Lajeunesse-Trempe et al. · Authors' conclusion

Names Iron and Omeprazole together in an interaction, co-administration, or pharmacokinetic context.

Limitations

What this evidence cannot tell you.

Search-based evidence indexes have real limits, and it is worth being explicit about them:

NutriStack

Track what you actually take.

NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Iron, Omeprazole, and several hundred other substances.

The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.

NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.