Skip to main content
MyDeficienciesMyDeficiencies
All medications
Supported by MyDeficiencies
Proton Pump Inhibitor (Acid Reducer)

Omeprazole

Also sold as Prilosec

Suppressed stomach acid impairs absorption of magnesium, B12, calcium, and iron; gut flora may shift upward into the small intestine (SIBO risk).

This page provides educational information about possible medication-related nutrient relationships. It does not diagnose a deficiency, establish that this medication caused a symptom, or replace qualified medical care.
Analyze This Medication View Research
Overview

About Omeprazole

Omeprazole belongs to the Proton Pump Inhibitor (Acid Reducer) class. Recognized brand names include Prilosec.

Suppressed stomach acid impairs absorption of magnesium, B12, calcium, and iron; gut flora may shift upward into the small intestine (SIBO risk).

MyDeficiencies does not provide dosing instructions, adverse-effect lists, or personalized medical advice. Always follow the guidance of your prescribing clinician and pharmacist.

Nutrient relationships

Possible Nutrient Relationships

  • Magnesium

    Stronger Evidence

    Required for 300+ enzymes, ATP stability, and neuromuscular function.

    Available evidence suggests Omeprazole may affect magnesium status. Individual responses vary.

  • Vitamin B12

    Moderate Evidence

    Acid is needed to cleave B12 from food protein.

    Available evidence suggests Omeprazole may affect vitamin b12 status. Individual responses vary.

  • Calcium

    Moderate Evidence

    Bone mineralization and muscle/nerve signaling.

    Available evidence suggests Omeprazole may affect calcium status. Individual responses vary.

  • Iron

    Emerging Evidence

    Oxygen transport and energy metabolism.

    Available evidence suggests Omeprazole may affect iron status. Individual responses vary.

How to read this page

Evidence Strength

Evidence labels reflect the current strength of available research, not a guarantee of individual outcomes:

  • Stronger Evidence — Consistent, replicated evidence across multiple well-designed studies.
  • Moderate Evidence — Supportive evidence with some variability across populations or study designs.
  • Emerging Evidence — Early or mechanistic signals that warrant continued study.

Read our full evidence framework →

Proposed mechanisms

How These Relationships May Occur

Irreversibly inhibits gastric H+/K+ ATPase, reducing stomach acid required for mineral solubilization, B12 cleavage from food protein, and microbial gatekeeping in the upper GI tract.

A proposed mechanism explains how a relationship might occur. It does not prove that a clinically meaningful deficiency occurs in every individual.

Body systems

Body Systems That May Be Relevant

  • Digestive & Microbiome

    Stronger Evidence

    Effects on gut acidity, motility, or microbial composition may influence nutrient absorption.

  • Copper–Iron Balance

    Moderate Evidence

    Trace mineral balance may be relevant.

  • Mitochondrial Energy

    Emerging Evidence

    Cofactors that support mitochondrial energy production may be relevant.

Symptoms and context

Symptoms and Context

Discussions around Omeprazole sometimes reference: Fatigue.

Symptoms such as fatigue, weakness, numbness, digestive changes, or mood changes can have many possible explanations. This page does not determine their cause.

Combinations reviewed

Reviewed Combinations

  • Omeprazole + Levothyroxine

    Moderate Evidence

    PPI-induced hypochlorhydria reduces levothyroxine dissolution and absorption.

    May cause sub-therapeutic thyroid hormone levels and recurrent hypothyroid symptoms.

  • Omeprazole + Metformin

    Moderate Evidence

    Both reduce vitamin B12 absorption — PPI via acid suppression, metformin via ileal B12-IF complex interference. Effects are additive.

    Compounded risk of B12 deficiency with neurologic symptoms (paresthesias, balance, fatigue).

For your next visit

Questions You May Want to Discuss

  • Could Omeprazole affect any nutrients over time in my situation?
  • Are there symptoms or risk factors that would make further evaluation appropriate?
  • Could diet, other medications, or health conditions affect this relationship?
  • Would laboratory testing be clinically appropriate for me?
  • Are there medication or supplement interactions I should understand?

These are conversation starters, not recommendations to request a specific test, supplement, or medication change.

Research

Research and Sources

See our evidence methodology for how sources are evaluated.

View MyDeficiencies research updates(research revisions are tracked centrally, including for Omeprazole)
Related nutrients

Related Nutrients

  • Magnesium
    Stronger Evidence
  • Vitamin B12
    Moderate Evidence
  • Calcium
    Moderate Evidence
  • Iron
    Emerging Evidence
Ready to go deeper

Explore Omeprazole in Your Report

Add Omeprazole to a MyDeficiencies analysis to view its reviewed nutrient relationships alongside other medications, supplements, symptoms, and relevant context.

Analyze This Medication Browse All Medications

Educational only. Not a diagnosis. Not a substitute for qualified medical care.