Calcium + Cholecalciferol

Fixed-dose combination: calcium salt (carbonate) plus vitamin D3

ATC code: A12AX (Calcium, combinations with other drugs)

Mechanism of action

Calcium carbonate provides elemental calcium (40% by weight) for bone mineralization. Cholecalciferol (vitamin D3) is converted in the liver to 25(OH)D and in the kidney to active 1,25(OH)2D. The active metabolite enhances intestinal calcium absorption and renal reabsorption, supporting osteoid mineralization. The combination corrects deficiency of both substrates without which osteoporosis therapy fails.

Indications

Osteoporosis

First line

Prevention and treatment of osteoporosis combined with disease-modifying therapy (bisphosphonates, denosumab, romosozumab). Per NOF 2022 and SEIOMM 2022, without adequate calcium and vitamin D any osteoporosis therapy loses efficacy. Dose: 1000-1500 mg elemental calcium + 800-1000 IU vitamin D3 per day, in two divided doses with meals. Do not co-administer calcium with bisphosphonates – separate by at least 2 hours. Baseline 25(OH)D – correct deficiency with cholecalciferol monotherapy first.

Sources

AEMPS: Ficha técnica de Calcio + Colecalciferol (2024)

Marketing claims without evidence base

The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.

Anti-aging and longevity

Not recommended

Calcium + vitamin D is often marketed to all adults for strong bones, immunity, and longevity. Per NOF 2022, 2018, and SEIOMM 2022, in healthy adults without osteoporosis, prior low-energy fractures, or confirmed vitamin D deficiency, daily supplementation does not reduce fracture risk or improve survival. High calcium intake (>1500 mg/day from diet plus supplements) increases kidney-stone risk and, by some meta-analyses, cardiovascular events. If prescribed for prevention without osteoporosis or vitamin D deficiency, consider getting a second opinion and a DXA scan.

Sources

Practical notes

Timing and administration

Take with meals (calcium carbonate absorbs best in acidic gastric environment). Do not co-administer with iron, levothyroxine, or bisphosphonates – separate by at least 2 hours.

Monitoring

Serum calcium and 25(OH)D every 6-12 months. If calcium >10.5 mg/dL, reassess the dose. Use with caution in chronic kidney disease.

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Safety

Contraindications

Hypercalcemia, hypercalciuria
Severe renal impairment
Vitamin D toxicity
Nephrocalcinosis, calcium-stone disease
Sarcoidosis and other granulomatous diseases (hypercalcemia risk)

Serious adverse effects

Hypercalcemia (long-term high-dose)
Kidney stones
Milk-alkali syndrome with antacid co-use

Common adverse effects

Constipation
Bloating
Nausea
Dry mouth

PregnancyFDA B

Compatible. Used to meet physiological requirements in pregnancy (per ACOG 2018, 1000-1300 mg calcium and 600 IU vitamin D daily). Do not exceed the dose.

Breastfeeding

Fully compatible. Hale L1. Covers nursing mother's physiological needs (1300 mg calcium, 600 IU vitamin D).

Calculate RID

Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.

Frequently asked

What is Calcium + Cholecalciferol used for?

Calcium + Cholecalciferol is evaluated for the following indications with varying evidence strength: Osteoporosis (evidence tier A), Anti-aging and longevity (evidence tier D). See the full indication matrix with dosing and citations above on this page.

What are the side effects of Calcium + Cholecalciferol?

Common side effects of Calcium + Cholecalciferol (≥ 1 in 100): Constipation, Bloating, Nausea, Dry mouth. See the Safety section for uncommon and serious reactions.

Is Calcium + Cholecalciferol safe during pregnancy?

FDA category B. Compatible. Used to meet physiological requirements in pregnancy (per ACOG 2018, 1000-1300 mg calcium and 600 IU vitamin D daily). Do not exceed the dose.

Is Calcium + Cholecalciferol compatible with breastfeeding?

Fully compatible. Hale L1. Covers nursing mother's physiological needs (1300 mg calcium, 600 IU vitamin D).

Who should not take Calcium + Cholecalciferol?

Calcium + Cholecalciferol is contraindicated in: Hypercalcemia, hypercalciuria; Severe renal impairment; Vitamin D toxicity; Nephrocalcinosis, calcium-stone disease; Sarcoidosis and other granulomatous diseases (hypercalcemia risk). Full list in the Safety section.

Mechanism of action

Indications

Osteoporosis

First line

Sources

AEMPS: Ficha técnica de Calcio + Colecalciferol (2024)

Practical notes

Timing and administration

Take with meals (calcium carbonate absorbs best in acidic gastric environment). Do not co-administer with iron, levothyroxine, or bisphosphonates – separate by at least 2 hours.

Monitoring

Serum calcium and 25(OH)D every 6-12 months. If calcium >10.5 mg/dL, reassess the dose. Use with caution in chronic kidney disease.

Safety

Contraindications

Hypercalcemia, hypercalciuria
Severe renal impairment
Vitamin D toxicity
Nephrocalcinosis, calcium-stone disease
Sarcoidosis and other granulomatous diseases (hypercalcemia risk)

Serious adverse effects

Hypercalcemia (long-term high-dose)
Kidney stones
Milk-alkali syndrome with antacid co-use

Common adverse effects

Constipation
Bloating
Nausea
Dry mouth

PregnancyFDA B

Compatible. Used to meet physiological requirements in pregnancy (per ACOG 2018, 1000-1300 mg calcium and 600 IU vitamin D daily). Do not exceed the dose.

Breastfeeding

Fully compatible. Hale L1. Covers nursing mother's physiological needs (1300 mg calcium, 600 IU vitamin D).

Calculate RID

Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.

Frequently asked

What is Calcium + Cholecalciferol used for?

What are the side effects of Calcium + Cholecalciferol?

Common side effects of Calcium + Cholecalciferol (≥ 1 in 100): Constipation, Bloating, Nausea, Dry mouth. See the Safety section for uncommon and serious reactions.

Is Calcium + Cholecalciferol safe during pregnancy?

FDA category B. Compatible. Used to meet physiological requirements in pregnancy (per ACOG 2018, 1000-1300 mg calcium and 600 IU vitamin D daily). Do not exceed the dose.

Is Calcium + Cholecalciferol compatible with breastfeeding?

Fully compatible. Hale L1. Covers nursing mother's physiological needs (1300 mg calcium, 600 IU vitamin D).

Who should not take Calcium + Cholecalciferol?