Can You Take Calcium and Ciprofloxacin Together?

Calcium can reduce how much ciprofloxacin your body absorbs -- FDA labeling recommends spacing them several hours apart.

Use cautionEvidence: High

What the interaction means

Ciprofloxacin's FDA prescribing information states: "Concurrent administration of a quinolone, including ciprofloxacin, with multivalent cation-containing products such as magnesium/aluminum antacids... or products containing calcium, iron, or zinc may substantially decrease its absorption." The label specifies: "Ciprofloxacin should be administered at least 2 hours before or 6 hours after... other products containing calcium, iron or zinc."

Why it may happen

Calcium can bind with ciprofloxacin in the gastrointestinal tract, substantially decreasing how much of the antibiotic is absorbed.

Practical context

The label's own spacing guidance is asymmetric -- at least 2 hours before, or 6 hours after -- rather than a single symmetric interval, so no single spacing-minutes figure is published here.

What the sources say

Last reviewed 2026-08-22

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.

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