Caltrac

Calcium (625mg) + Vitamin D3 (125IU)
Price: ₹100 - ₹160 for 15 tablets
Mfr: Micro Labs Limited | Form: Tablet

📋 Clinical Overview

A fixed-dose combination supplement containing 625mg of elemental calcium (as calcium carbonate) and 125 International Units (IU) of Vitamin D3 (Cholecalciferol). This combination is primarily used for the prevention and treatment of calcium and vitamin D deficiencies. Calcium is essential for bone mineralization, muscle contraction, nerve conduction, and blood coagulation. Vitamin D3 enhances intestinal absorption of calcium and phosphorus, promotes bone mineralization, and regulates serum calcium levels. In the Indian context, this formulation is widely used to address widespread nutritional deficiencies, particularly in postmenopausal women, the elderly, and individuals with limited sun exposure.

💊 Dosage & Administration

Adult: One tablet once daily, preferably with or after a meal. For osteoporosis/osteomalacia: Often used as adjunctive therapy. The 125IU Vitamin D3 dose is typically for maintenance; deficiency treatment requires higher doses.

Note: Swallow whole with a full glass of water. Take with or immediately after a meal to enhance calcium absorption and reduce gastric irritation. Do not take with high-oxalate foods (spinach, sweet potatoes) or high-fiber meals simultaneously, as they can bind calcium. Space by at least 2 hours from other medications like tetracyclines, quinolones, bisphosphonates, levothyroxine, and iron supplements.

⚠️ Contraindications

  • Hypercalcemia (elevated serum calcium)
  • Hypervitaminosis D
  • Severe renal impairment (eGFR <30 mL/min) without medical supervision due to risk of hypercalcemia and metastatic calcification
  • Known hypersensitivity to any component

🔬 Mechanism of Action

This combination works synergistically. Calcium provides the essential cation required for bone hydroxyapatite crystal formation and numerous physiological functions. Vitamin D3, after conversion to calcitriol, acts as a hormone that binds to the Vitamin D Receptor (VDR) in the intestines, bones, and kidneys. This genomic action increases the expression of calcium-binding proteins (e.g., calbindin) in enterocytes, facilitating active transcellular calcium absorption. It also promotes renal calcium reabsorption and, in conjunction with PTH, stimulates bone resorption to mobilize calcium when needed.

🤕 Side Effects

  • Constipation
  • Abdominal pain/discomfort
  • Bloating
  • Flatulence
  • Nausea

🤰 Special Populations

Pregnancy: Category A (Australian) / Generally considered safe. Calcium and Vitamin D requirements increase during pregnancy. This dose is safe for supplementation. Excessive doses (>4000 IU/day Vitamin D) should be avoided. Consult a physician.

Driving: No effect on ability to drive or operate machinery.

🔄 Drug Interactions

Thiazide Diuretics (e.g., Hydrochlorothiazide)Reduce renal calcium excretion, increasing risk of hypercalcemia.Major
Oral Bisphosphonates (e.g., Alendronate)Calcium supplements interfere with absorption. Administer at least 2 hours apart.Major
LevothyroxineCalcium carbonate can decrease its absorption. Separate administration by at least 4 hours.Major
Oral Quinolone/Tetracycline AntibioticsCalcium binds to these drugs, forming insoluble complexes and reducing antibiotic absorption. Separate doses by 2-3 hours.Major
Iron SupplementsCalcium can inhibit iron absorption. Take at different times of the day.Moderate
Corticosteroids (e.g., Prednisolone)Reduce calcium absorption and increase excretion, potentially requiring higher calcium/vitamin D intake.Moderate
OrlistatMay reduce absorption of fat-soluble vitamins including Vitamin D.Moderate
Phenytoin, Phenobarbital, CarbamazepineInduce hepatic CYP450 enzymes, accelerating metabolism of Vitamin D to inactive metabolites, leading to deficiency.Moderate
DigoxinHypercalcemia can potentiate digoxin toxicity, leading to arrhythmias. Monitor serum calcium and digoxin levels.Major

🔁 Alternatives to Caltrac

Same composition (Calcium (625mg) + Vitamin D3 (125IU)), different brands:

Shelcal 500 Calcirol Calcium-D Calcarea Ostocalcium