Can I Take These?

Can You Take Ciprofloxacin and Magnesium Together?

Magnesium 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, resulting in serum and urine levels considerably lower than desired." The label specifies: "Ciprofloxacin should be administered at least 2 hours before or 6 hours after magnesium/aluminum antacids... or other products containing calcium, iron or zinc."

Why it may happen

Magnesium 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 magnesium, or 6 hours after -- rather than a single symmetric interval, so no single spacing-minutes figure is published here; follow the asymmetric guidance above.

What the sources say

Ciprofloxacin Tablet — FDA Prescribing Information — Rising Pharmaceuticals, Inc. (via DailyMed, U.S. National Library of Medicine)

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.

Related interactions