Calcium

28 interactions 1 explained in plain English
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 11, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Baloxavir Marboxil Digoxin Dolutegravir Levothyroxine
4 Major 19 Moderate 5 Minor
All (28) Major (4) Moderate (19) Minor (5)

Major

Calcium Baloxavir Marboxil Xofluza Decreased baloxavir concentration Details Calcium Digoxin Cardoxin® A serious risk of arrhythmia and cardiovascular collapse Details Calcium Dolutegravir Juluca® (as a combination product containing dolutegravir, rilpivirine) Reduced dolutegravir exposure and reduced efficacy of dolutegravir Details Calcium Levothyroxine Ermeza Reduced levothyroxine absorption, reduced efficacy of levothyroxine and an increased risk of hypothyroidism Details

Moderate

Calcium Aspirin Acuprin® Decreased salicylate effectiveness Details Calcium Aspirin Rectal Aspirin Decreased salicylate effectiveness Details Calcium Cefpodoxime Banan® Decreased cefpodoxime effectiveness Details Calcium Deferiprone Ferriprox Decreased absorption of minerals Details Calcium Delafloxacin Baxdela Decreased delafloxacin efficacy Details Calcium Delafloxacin Injection Baxdela Decreased delafloxacin efficacy Details Calcium Demeclocycline Declomycin® Reduced efficacy of tetracyclines Details Calcium Doxycycline Injection Acticlate Reduced efficacy of tetracyclines Details Calcium Ibandronate Boniva Decreased ibandronate effectiveness Details Calcium Ibandronate Injection Boniva Decreased ibandronate effectiveness Details Calcium Levofloxacin Levaquin Decreased oral levofloxacin effectiveness Details Calcium Levofloxacin Injection Levaquin Decreased oral levofloxacin effectiveness Details Calcium Minocycline Amzeeq Reduced efficacy of minocycline Details Calcium Minocycline Topical Amzeeq Reduced efficacy of minocycline Details Calcium Ofloxacin Floxin® Decreased oral ofloxacin effectiveness Details Calcium Ofloxacin Ophthalmic Ocuflox Decreased oral ofloxacin effectiveness Details Calcium Ofloxacin Otic Floxin® Otic Decreased oral ofloxacin effectiveness Details Calcium Omadacycline Nuzyra Decreased effectiveness of omadacycline Details Calcium Omadacycline Injection Nuzyra Decreased effectiveness of omadacycline Details

Minor

Calcium Atenolol Tenormin Explained Reduced effectiveness of atenolol Details Calcium Alendronate Binosto Reduced alendronate absorption Details Calcium Bisacodyl Alophen Reformulated Jan 2008 Decreased effectiveness of bisacodyl Details Calcium Bisacodyl Rectal Bisac-Evac Decreased effectiveness of bisacodyl Details Calcium Etidronate Didronel® Reduced etidronate absorption Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.