Drug & supplement interaction

Magnesium + Etidronate Disodium

Etidronate Disodium brand names: Didronel, Didrocal.

Moderate Interaction
The bottom line Moderate

Magnesium has a moderate interaction with Etidronate Disodium. Magnesium can decrease absorption of bisphosphonates.

Read the full interaction report
SeverityModerate
LikelihoodProbable
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Magnesium and Etidronate Disodium

Here is the interaction we found between these two, with the evidence behind it.

Moderate

BISPHOSPHONATES

Why this applies to Etidronate Disodium

Etidronate Disodium falls under BISPHOSPHONATES — the group Magnesium interacts with.

Magnesium can decrease absorption of bisphosphonates.
Cations, including magnesium, can decrease bisphosphonate absorption. Advise patients to separate doses of magnesium and these drugs by at least 2 hours.
Severity Moderate Likelihood Probable Evidence B

Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist: magnesium and etidronate don't get along in your stomach. Etidronate is already a tricky drug to absorb, and minerals like magnesium grab onto it and form clumps your gut can't take up well. The result is that less of your etidronate actually gets into your body, which can mean it doesn't do its job of strengthening bone in Paget's disease or curbing extra bone growth after hip or spinal injury.

The good news is that this is easy to manage. You don't have to give up either one. Just space them out, taking your magnesium at least 2 hours apart from your etidronate dose. This is a well-recognized interaction, so check with your pharmacist or doctor about the best timing for your full medication list.

References
  1. Dunn CJ, Goa KL. Risedronate: a review of its pharmacological properties and clinical use in resorptive bone disease. Drugs 2001;61:685-712..

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Magnesium Also Interacts With Other Medications

Magnesium has 6 major, 174 moderate, 114 minor known drug interactions in our database — the Etidronate Disodium one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Magnesium

Covers the 2,830 medications we’ve checked against Magnesium. Pick one to open its full report.

From our Q&A

Questions About Magnesium or Etidronate Disodium

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Magnesium or Etidronate Disodium, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Etidronate Disodium

This page covers Magnesium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Etidronate Disodium page lists 23 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Calcium (moderate), Coffee Charcoal (moderate), Dolomite (moderate) and European Mandrake (moderate).

By severity: 1 major · 13 moderate · 9 minor.

From our pharmacist’s overview on the Etidronate Disodium page

“Etidronate disodium (Didronel) is a bisphosphonate prescribed for Paget's disease of bone, a drug already so poorly absorbed that anything blocking its uptake matters, which is why I read this list with genuine caution. Nearly every one of the 23 ingredients on file interferes with absorption in some way.”

Reviewed by 2 · Jul 18, 2026

Open the Etidronate Disodium interaction page

One more smart check

Taking Magnesium as Part of a Dietary Supplement Product? Check It for Interactions

We hold 29,717 real supplement products containing Magnesium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Magnesium. Your product may carry other ingredients that interact with Etidronate Disodium too, on top of Magnesium — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Magnesium and Etidronate Disodium Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Magnesium
Top 10

#5 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Etidronate Disodium
Steady interest

#1,535 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Magnesium

What is Magnesium?

Magnesium
  • Preventing or treating magnesium deficiency
  • Constipation
  • Muscle cramps
  • Sleep support
  • Anxiety and stress
  • Migraine prevention

Magnesium is an essential mineral your body needs for muscles, nerves, blood pressure, and many other functions, and supplements are useful for preventing or correcting deficiency. Some other uses, like easing constipation or preventing migraines, have reasonable support, while uses for sleep and anxiety are less proven. It is generally safe for most healthy people at recommended amounts, but talk to your pharmacist or doctor before starting, especially if you have kidney problems.

Read the full Magnesium monograph & all interactions
Medication

About Etidronate

What Is Etidronate Used For?

Brand names: Didronel, Didrocal

  • Etidronate is used to treat Paget's disease of bone (a condition in which the bones are soft and weak and may be deformed, painful, or easily broken) and to prevent and treat heterotopic ossification (growth of bone tissue in an area of the body other than the skeleton) in people who have had total hip replacement surgery (surgery to replace the hip joint with an artificial joint) or in people who have had an injury to the spinal cord. Etidronate is in a class of medications called bisphosphonates. It works by slowing the breakdown of old bone and the formation of new bone.

See full Etidronate drug information
Keep checking

Other Drugs & Magnesium

Browse every other medication we’ve checked against Magnesium — both the ones with a known interaction and the ones without. Select any drug for the full detail.

6Major
174Moderate
114Minor
2,535No known interaction
Major

6 interactions

Moderate

174 interactions

Showing 60 of 174 moderate interactions — see all 174 on the Magnesium page.

Minor

114 interactions

Showing 60 of 114 minor interactions — see all 114 on the Magnesium page.

No interaction 2,535 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Magnesium and Etidronate Disodium Together: Common Questions

Can you take Magnesium with Etidronate Disodium?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Magnesium and Etidronate Disodium interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Etidronate Disodium and Magnesium?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.