Generic
Calcium Carbonate
120 brands available in the market
At a glance
Calcium Carbonate is a calcium supplement and antacid used for the treatment of heartburn, indigestion, stomach upset, calcium deficiency, hypocalcemia, and hyperphosphatemia in chronic renal failure. It neutralizes gastric acid and helps replenish calcium deficiency.
Description
Calcium Carbonate is a calcium supplement and antacid used for heartburn, indigestion, stomach upset, calcium deficiency, hypocalcemia, and hyperphosphatemia. 250 mg or 500 mg tablets are used for calcium deficiency; 1000 mg tablets are used for rapid relief of acid-related conditions.
Calcium Carbonate reacts with gastric acid to produce salt and water. Chemical reaction: CaCO₃ + 2HCl = CaCl₂ + H₂O + CO₂. Two grams of calcium carbonate readily bring 100 mL of hydrochloric acid to a pH above 6. Increased gastric pH reduces pepsin activity. Up to 30% of the oral calcium load may be absorbed.
Indications
- Heartburn
- Indigestion
- Stomach upset
- Calcium deficiency
- Hypocalcemia
- Hyperphosphatemia in chronic renal failure
- Calcium supplement
- Osteoporosis prevention
- Pregnancy and lactation calcium supplementation
Therapeutic class
Specific mineral preparations
Pharmacological class
Calcium Supplement / Antacid
Pharmacology
Calcium Carbonate reacts with gastric acid to produce salt and water. Two grams of calcium carbonate readily bring 100 mL of hydrochloric acid to a pH above 6. Increased gastric pH reduces pepsin activity. Up to 30% of the oral calcium load may be absorbed.
Mechanism of action
Calcium carbonate neutralizes gastric acid rapidly and effectively. However, it may adversely activate calcium-dependent processes, leading to gastric and hydrochloric acid secretion. It can induce rebound acid secretion and, with prolonged high doses, may cause hypercalcemia, alkalosis, and milk-alkali syndrome.
Dosage
Adults (Hyperacidity): 1-2 tablets as needed, up to a maximum of 16 tablets/day. Tablets may be sucked or chewed.
Hyperphosphatemia in chronic renal failure: Initial dose: 2.5 g/day, up to 17 g/day in divided doses.
Calcium supplement (Osteoporosis prevention): 1250-3750 mg Calcium Carbonate (500-1500 mg calcium)/day.
Pregnancy and lactation: 1200-1500 mg calcium/day.
Renal impairment (CrCl <25 mL/min): Dose adjustments may be needed depending on serum calcium levels.
Children: Half the adult dose.
Administration
May be taken with or without food. Take with meals for better absorption. Avoid taking with large amounts of fiber-rich food. In chronic renal failure, take with meals to maximize phosphate binding.
Missed dose
If you miss a dose, take it as soon as you remember. Skip the missed dose if it is almost time for your next dose. Do not double the dose.
Side effects
Common side effects: Anorexia, nausea, vomiting, constipation, flatulence.
Serious (long-term/high doses): Hypercalcemia, metabolic alkalosis, milk-alkali syndrome, tissue calcification. Gastric hypersecretion and acid rebound may occur with prolonged use.
Hypercalcemia may occur with large doses in chronic renal failure patients.
Precautions & warnings
- Caution in renal impairment, hypoparathyroidism, and hypercalcemia-associated diseases.
- Calcium absorption is impaired in achlorhydria; use an alternative calcium salt and take with food.
- Caution in patients with history of kidney stones.
- Contraindicated in calcium renal calculi or history, hypercalcemia, hypophosphatemia, and suspected digoxin toxicity.
- Lactation: Safe; crosses the placenta and appears in breast milk.
Contraindications
- Calcium renal calculi or history of renal calculi
- Hypercalcemia
- Hypophosphatemia
- Suspected digoxin toxicity
- Zollinger-Ellison syndrome
- Concomitant digoxin therapy (requires careful monitoring of serum calcium levels)
Drug interactions
- Thiazide diuretics or vitamin D: May lead to milk-alkali syndrome and hypercalcemia.
- Corticosteroids: Decreased calcium absorption.
- Tetracyclines, atenolol, iron, quinolones, alendronate, sodium fluoride, zinc, calcium-channel blockers: Decreased absorption.
- Digitalis glycosides (digoxin): Enhances cardiac effects and may precipitate digitalis intoxication (if systemic hypercalcemia occurs).
Food interactions
Take with meals for better absorption. Avoid taking with large amounts of fiber-rich food.
Use in pregnancy
Safe during pregnancy (Category C). Calcium supplementation and antacid therapy are widely used during pregnancy. 1200-1500 mg calcium/day is recommended.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Safe during lactation; crosses the placenta and appears in breast milk. Calcium-containing drugs can be used in lactating women.
Pediatric use
Safe and effective in children (extensively studied in children with chronic renal failure). Children's dose is half the adult dose.
Geriatric use
Elderly patients (especially with renal failure) may experience constipation; monitoring of serum calcium and phosphate is indicated.
Renal / hepatic impairment
Hepatic impairment: No special precautions required, but consult your physician.
Overdose effects
Overdose symptoms: Nausea, vomiting, dry mouth, loss of appetite, stomach cramps, diarrhea, headache, constipation. Severe cases: hypercalcemia, milk-alkali syndrome, tissue calcification.
Storage conditions
Store in a cool, dry place at controlled room temperature. Keep out of reach of children.
Chemical structure
Calcium Carbonate