Drug & supplement interaction

Strontium + Ciprofloxacin

Ciprofloxacin brand names: Cipro, Ciprobay, Cipro XR, Ciloxan, Cipro IV, and others.

Moderate Interaction
The bottom line Moderate

Strontium has a moderate interaction with Ciprofloxacin. Theoretically, strontium might decrease the absorption of quinolone antibiotics.

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

Strontium and Ciprofloxacin

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

Moderate

QUINOLONE ANTIBIOTICS

Why this applies to Ciprofloxacin

Ciprofloxacin falls under QUINOLONE ANTIBIOTICS — the group Strontium interacts with.

Theoretically, strontium might decrease the absorption of quinolone antibiotics.
Strontium is a divalent cation with similar properties to calcium. It is likely to form complexes with quinolones in the gastrointestinal (GI) tract, preventing absorption of the antibiotic. Recommend taking strontium supplements at least 2 hours before or after quinolones to avoid an interaction.
Severity Moderate Likelihood Probable Evidence D

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 practical concern with taking strontium alongside ciprofloxacin (Cipro). Strontium behaves a lot like calcium in your gut, and these minerals tend to grab onto antibiotics like Cipro and form a clump that your body can't absorb well. If that happens, less of the antibiotic actually gets into your bloodstream, which could mean your infection isn't treated as effectively. This isn't about extra side effects; it's about the drug possibly not working as well as it should.

The good news is the fix is simple. Separating the two doses (taking strontium at least 2 hours before or after your Cipro) usually keeps them from binding together. This is based on how these minerals behave rather than hard clinical studies, but since beating an infection matters, it's worth being careful. Run your full schedule by your pharmacist or doctor to be safe.

References
  1. Protelos European Summary of Product Characteristics. Les Laboratoires Servier, 2006. Available at: www.servier.com/pro/osteoporose/protelos/protelos_spc.asp. (Accessed 01 August 2006).

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

Strontium Also Interacts With Other Medications

Strontium has 100 moderate known drug interactions in our database — the Ciprofloxacin 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 Strontium

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

From our Q&A

Questions About Strontium or Ciprofloxacin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Strontium or Ciprofloxacin, 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 Ciprofloxacin

This page covers Strontium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ciprofloxacin page lists 163 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Apple (major), Asarabacca (major), Beer (major) and Grapefruit (major).

By severity: 8 major · 133 moderate · 22 minor.

From our pharmacist’s overview on the Ciprofloxacin page

“A glass of apple or grapefruit juice can sharply cut how much ciprofloxacin (Cipro) your body absorbs, because these juices block a transporter the antibiotic needs to reach the bloodstream. That is one of eight major-rated risks among the 163 supplement and herbal ingredients on file, and I treat this list as a genuine warning rather…”

Reviewed by 2 · Jul 18, 2026

Open the Ciprofloxacin interaction page

One more smart check

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

We hold 347 real supplement products containing Strontium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Strontium. Your product may carry other ingredients that interact with Ciprofloxacin too, on top of Strontium — 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 Strontium and Ciprofloxacin 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 Strontium
Top 25%

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

29 days ago today
Medication Ciprofloxacin
Top 5%

#69 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 Strontium

What is Strontium?

  • Bone health and osteoporosis
  • Reducing fracture risk
  • Tooth sensitivity (in some toothpastes)
  • Supporting bone density

Strontium is a mineral that has been studied mainly for bone health and osteoporosis. The prescription form (strontium ranelate) showed benefit for fracture risk but carries serious heart-related safety concerns, while the over-the-counter supplement form (strontium citrate) has much less evidence. Talk to your doctor or pharmacist before using it, especially if you have heart disease or are at risk for blood clots.

Read the full Strontium monograph & all interactions
Medication

About Ciprofloxacin

What Is Ciprofloxacin Used For?

Brand names: Cipro, Ciprobay, Cipro XR, Ciloxan, Cipro IV, Otiprio

Ciprofloxacin treats infections caused by susceptible bacteria. It does not work on viruses.

Tablets and IV injection cover many body-wide infections, such as skin, bone and joint, abdominal, respiratory and urinary tract infections. Eye products treat corneal ulcers and bacterial conjunctivitis. Ear drops treat acute otitis externa (outer ear canal infection).

See full Ciprofloxacin drug information
Keep checking

Other Drugs & Strontium

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

0Major
100Moderate
0Minor
2,729No known interaction
Moderate

100 interactions

Showing 60 of 100 moderate interactions — see all 100 on the Strontium page.

No interaction 2,729 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 Strontium and Ciprofloxacin Together: Common Questions

Can you take Strontium with Ciprofloxacin?
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 Strontium and Ciprofloxacin 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 Ciprofloxacin and Strontium?

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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.