About calcium carbonate
Calcium supplement and antacid
Used for
- Preventing or treating calcium deficiency
- Relief of heartburn, acid indigestion, and upset stomach
Usual adult dose
For calcium deficiency, commonly 500–1,500 mg elemental calcium daily in divided doses. As an antacid, follow product directions.
Usual dose in children
For deficiency, doses depend on age and dietary calcium; clinician guidance is needed. Not usually used as an antacid in young children.
Common side effects
- Constipation
- Gas or bloating
- Nausea
- High blood calcium with excessive use
Important warnings
- Check the label: 500 mg calcium carbonate provides about 200 mg elemental calcium.
- Separate from iron, thyroid medicine, and some antibiotics; ask a pharmacist about timing.
- Use caution with kidney disease, kidney stones, or high blood calcium.
- Frequent antacid use can mask persistent symptoms.
Pregnancy
Generally considered safe when needed at recommended doses; avoid excessive total calcium intake.
Breastfeeding
Generally compatible at recommended doses.
Interactions
- Levothyroxine: calcium can reduce absorption; separate doses.
- Tetracycline and quinolone antibiotics: calcium can reduce absorption.
- Iron: calcium may reduce absorption.
- Bisphosphonates: calcium can reduce absorption.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.