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Drug reference

calcium citrate

Calcium salt · Calcium supplement

Calcium saltCalcium supplement
CDSCO approved
EXCRETION
—
not curated
INTERACTIONS
—
none in our sources
PREGNANCY
—
not curated

Mechanism

Provides elemental calcium for physiological functions. It is soluble in the presence of HCl.

Indications

Tetany (long-term oral therapy)Dietary supplement (growing children, pregnant, lactating and menopausal women)Osteoporosis (adjuvant role to alendronate/HRT/raloxifene)

Dosing

Adult
1–1.5 g daily (oral, general calcium allowance); specific dietary allowances: Men 25–65 yr, women 25–50 yr and 51–65 yr if taking HRT: 1.0 g; Women 51–65 yr not taking HRT, every one > 65 yr: 1.5 g
Pediatric
Children 1–10 yr: 0.8–1.2 g; Young adult 11–24 yr: 1.2–1.5 g

Pharmacokinetics

Bioavailability
Absorption in patients taking PPIs/H2 blockers and elderly is satisfactory.

Side effects

Common
ConstipationBloatingExcess gas
Serious
  • Myocardial infarction (27% higher incidence in subjects receiving calcium supplements)

Drug interactions

Ciprofloxacin
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Doxycycline
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Levofloxacin
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Minocycline
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Moxifloxacin
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Norfloxacin
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Ofloxacin
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Tetracycline
Moderate
Textbook-cited

Therapeutic failure of the antibiotic

Stagger administration by 2-3 hours

Source: KDT 7e · p949

Related guidelines

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Textbook-sourced·Sources: KD Tripathi 7e·Updated: 2026-05-10