Supplements and Esomeprazole.
Esomeprazole, sold under the brand name Nexium, is a proton pump inhibitor (PPI): it suppresses gastric acid production by inhibiting the H+/K+ ATPase pump.
Esomeprazole is a proton pump inhibitor (PPI). The class binds irreversibly to the H+/K+ ATPase in gastric parietal cells, suppressing acid secretion for 12 to 24 hours per dose. Sustained low gastric acid has documented downstream effects on nutrient absorption. Vitamin B12, which needs acid to dissociate from food protein. Magnesium, where hypomagnesaemia from PPI use is in NICE guidance. Iron, especially the form found in plant sources. And calcium, with the bone fracture signal in long observational data. NICE recommends annual review of PPI indication and stepping down where possible. Supplement interactions sit mostly in the absorption category, not the CYP-metabolism category. CYP2C19 inhibition varies across the class. Omeprazole is the strongest, with lansoprazole and pantoprazole quieter. This matters for clopidogrel when the two are given alongside each other. Anyone on a PPI more than two years benefits from a B12 and magnesium check.
Below are the 9 documented pairs we have explicitly assessed against Esomeprazole in the Distil database: 8 amber and 1 green. The pairs cluster around 2 mechanisms: Absorption interference and CYP induction. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.
Documented interactions
Absorption interference
Calcium carbonate, the most common supplement form, needs stomach acid to dissolve, so esomeprazole can reduce how much calcium you absorb from it. Calcium citrate does not depend on stomach acid and is the better choice on a long-term PPI. If you stay on carbonate, taking it with food rather than on an empty stomach also helps.
Non-haem iron from supplements absorbs less well in a low-acid stomach, so chronic esomeprazole use reduces iron uptake from a standard ferrous sulphate or ferrous fumarate tablet. Iron bisglycinate is less pH-dependent and a better choice on a long-term PPI. Taking iron in the morning on an empty stomach with vitamin C also helps. Always confirm ferritin is in the deficient range before supplementing iron.
Long-term esomeprazole use is associated with low blood magnesium in about 1 in 5 chronic users. Supplementing magnesium is generally helpful, but if you have heart, kidney, or muscle symptoms on long-term esomeprazole, ask your GP for a magnesium blood test.
Long-term esomeprazole use is associated with low blood magnesium in about 1 in 5 chronic users. Supplementing magnesium is generally helpful, but if you have heart, kidney, or muscle symptoms on long-term esomeprazole, ask your GP for a magnesium blood test.
Long-term esomeprazole use is associated with low blood magnesium in about 1 in 5 chronic users. Magnesium L-threonate is still elemental magnesium, so supplementing is generally helpful, but if you have heart, kidney, or muscle symptoms on long-term esomeprazole, ask your GP for a magnesium blood test.
A B complex contains vitamin B12, and long-term esomeprazole reduces stomach acid and slows how well your body absorbs B12 from food. After about two years of daily use, B12 deficiency becomes notably more likely, and a standard B complex dose may not fully offset it. If you take esomeprazole long term, ask your GP about an annual B12 blood test.
Long-term esomeprazole use reduces stomach acid and slows how well your body absorbs vitamin B12 from food. After about two years of daily use, B12 deficiency becomes notably more likely. Good to know: a B12 supplement gets around this, because supplement B12 does not need stomach acid to be absorbed. If you take esomeprazole long term, ask your GP about an annual B12 blood test.
This is worth knowing rather than a problem. Vitamin C is less stable when the stomach is less acidic, and acid-lowering medicines like esomeprazole modestly reduce the amount of vitamin C in your blood. The drop is small, it is the medicine affecting the vitamin rather than the other way round, and it does not stop you taking a vitamin C supplement. If anything, people on long-term acid-lowering treatment are the ones who may benefit most from keeping a good vitamin C intake.
CYP induction
Esomeprazole is closely related to omeprazole and is cleared by the same enzyme that ginkgo can speed up, so ginkgo may make esomeprazole work less well, mainly at higher ginkgo doses. If your reflux or ulcer symptoms are not well controlled while taking both, mention the ginkgo to your GP or pharmacist.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.
How we grade severity, choose what's in scope, and what we exclude.
Every call on this page is reasoned. We publish the full rubric for severity tiers, the medication inclusion logic, the evidence grades we accept, and what we deliberately leave out. About three thousand words. Worth reading once if you use this tool more than occasionally.
Read the full methodologyWant this checked across everything you take?
This page checks the pairs you enter. The personalised Distil report goes further:
- the same graded, cited interaction check across your whole stack, not just the pairs you thought to type in
- where your current routine may be leaving you short of your goals
- the evidence-backed compounds worth adding, and the ones worth dropping
It's a paid report: £79, or £49 for the first 25 customers. The interactions check is one section of it, and you can read a real one in full before you buy.
See a real sample reportSomething missing?
If a supplement or medication you take isn't in our autocomplete, tell us. We go through what people flag every week and add what's missing.