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☀️ Calcium · Vitamin D3 · Essential micronutrients

Calcium & Vitamin D
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India · Deficiency · Rickets · Osteoporosis · Pregnancy · Paediatric · Shelcal · Calcirol · Uprise-D3 · Cholecalciferol

Deficiency: 60,000 IU weekly × 8wk Rickets: D3 + calcium ICMR · IAP · FOGSI aligned

Calcium & Vitamin D Calculator

☀️ Serum 25-OH Vitamin D interpretation (ng/mL)
Severe deficiency< 10 ng/mL
Deficiency10–19 ng/mL
Insufficiency20–29 ng/mL
Sufficient≥ 30 ng/mL
Recommended Dose
Loading dose
Maintenance dose
Duration
Recheck level
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ℹ️
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📊 Daily requirements (ICMR)
Infant 0–6mVit D 400 IU/day
Child 1–18yrVit D 600 IU · Ca 500–1300mg
Adult 19–50yrVit D 600 IU · Ca 600mg
Adult >50yrVit D 800–1000 IU · Ca 1200mg
PregnancyVit D 600–1000 IU · Ca 1200mg
BreastfeedingVit D 1500 IU · Ca 1200mg
🏷️ Indian brands
60,000 IU sachetCalcirol · Uprise-D3 · D-Rise
1000 IU capCholecalciferol · Calcitriol
Ca 500mg (carbonate)Shelcal 500 · Calcimax 500
Ca 1000mgShelcal 1000 · Ostocalcium
Ca + D3 comboShelcal-D · Calcimax D3
Drops (400 IU/ml)Adrigyl · Cholecalciferol drops
💡 Absorption tips

☀️ Vit D is fat-soluble — take with a fat-containing meal

🦴 Calcium carbonate: take with meals (needs acid for absorption)

🦴 Calcium citrate: can be taken on empty stomach — better for elderly / on PPIs

⚠️ Max single calcium dose: 500mg elemental (split doses)

⚠️ Vitamin D toxicity: levels >150 ng/mL — do not exceed upper safe limits

Calcium & Vitamin D Dosing Reference — India

IndicationVitamin D3 doseCalcium doseDurationGuideline
Vit D deficiency (<20 ng/mL)60,000 IU weekly × 8 weeks, then 60,000 IU monthly500–1000mg elemental/dayRecheck at 3 monthsICMR · Endocrine Society
Severe deficiency (<10 ng/mL)60,000 IU twice weekly × 6–8 weeks, then monthly1000mg/dayRecheck at 3 monthsEndocrine Society
Maintenance (>30 ng/mL)1,000–2,000 IU daily or 60,000 IU monthly500–600mg/dayOngoingICMR RDA
Nutritional rickets (child)60,000 IU weekly × 6–12 weeks (IAP)500mg elemental BD × 3 months6–12 weeks Vit D + 3m CaIAP rickets guidelines
Infant prophylaxis (breastfed)400 IU daily from day 15 until 2 yearsFrom complementary feedsUntil 2 yearsIAP · AAP
Osteoporosis (with bisphosphonate)800–1000 IU daily1000–1200mg elemental/dayOngoingIOF · BNF
Pregnancy — routine600–1000 IU/day or 60,000 IU monthly1200mg elemental/dayThroughout pregnancy + 6m postpartumFOGSI · WHO
Pre-eclampsia prevention1000 IU/day1500–2000mg/day (WHO)From 20 weeks if low intakeWHO · Cochrane

Vitamin D & Calcium Deficiency — India Clinical Guide

India has a paradoxical vitamin D deficiency crisis — despite abundant sunshine, studies show that 70–90% of Indians have inadequate vitamin D levels (25-OH Vit D <20 ng/mL). The reasons are multifactorial: skin pigmentation (melanin reduces UV synthesis), traditional clothing covering most skin, indoor occupational lifestyles, air pollution blocking UV-B, and the near-complete absence of natural dietary vitamin D in vegetarian Indian diets (vitamin D3 is found almost exclusively in oily fish, eggs, and fortified dairy — all poorly represented in the Indian diet).

The 60,000 IU sachet — India's standard dosing unit

Unlike Western countries where daily supplementation (1000–2000 IU/day) is standard, Indian practice overwhelmingly uses high-dose intermittent therapy. The 60,000 IU cholecalciferol sachet or capsule (Calcirol, Uprise-D3, D-Rise) has become the de facto standard supplementation unit in India — prescribed weekly for deficiency loading and monthly for maintenance. This is supported by Indian endocrinology consensus and is practical for the Indian healthcare context where daily compliance is lower. The loading phase is 8 weekly doses (total 480,000 IU) followed by monthly maintenance.

Nutritional rickets — calcium AND vitamin D

In India, nutritional rickets is frequently calcium-deficiency rickets rather than vitamin D-deficiency rickets — an important distinction because treatment requires high-dose calcium supplementation alongside vitamin D. The IAP rickets guidelines recommend calcium 500 mg elemental twice daily for 3 months in addition to vitamin D 60,000 IU weekly for 6–12 weeks. Without adequate calcium, vitamin D loading alone is insufficient for radiological healing. Signs of calcium-deficiency rickets: hypocalcaemia, positive Trousseau and Chvostek signs, and a diet predominantly based on cereals with limited dairy.

Vitamin D toxicity — upper safe limits

Vitamin D toxicity (hypervitaminosis D) occurs when serum 25-OH Vit D exceeds 150 ng/mL, causing hypercalcaemia, hypercalciuria, nephrocalcinosis, and eventually renal failure. The upper tolerable intake limit (UL) for adults is 4,000 IU/day for chronic use; safe upper limit for short-term treatment in deficiency is higher. With standard Indian protocols (60,000 IU weekly × 8 weeks = 480,000 IU loading), toxicity is extremely rare in adults. However, caution is required in sarcoidosis, granulomatous diseases, primary hyperparathyroidism, and in patients already on calcitriol — these conditions cause excessive conversion of vitamin D to its active form.

Frequently Asked Questions

How long does it take for vitamin D levels to normalise after starting supplements?+
With the standard 60,000 IU weekly loading protocol (8 doses), serum 25-OH Vit D levels typically reach the sufficient range (>30 ng/mL) within 8–12 weeks in most patients. Recheck the level 3 months after starting supplementation. Some patients — particularly the very obese (Vit D distributes into fat tissue), those with malabsorption, or those with very low baseline levels — may need extended loading. Do not recheck earlier than 6–8 weeks as levels peak 3–5 days after each dose and decline before the next.
Why should calcium doses be split — not taken all at once?+
The intestine can only absorb approximately 500 mg elemental calcium at a time. Taking more than 500 mg in a single dose does not increase absorption — the excess is wasted. For patients requiring 1000–1200 mg/day, split into two doses of 500–600 mg each (morning and evening). Taking with meals improves calcium carbonate absorption (needs gastric acid). For patients on PPIs or with achlorhydria, calcium citrate is preferred as it does not require acid for absorption.
Can too much vitamin D cause harm?+
Yes. Vitamin D toxicity (hypervitaminosis D) occurs with levels >150 ng/mL and causes hypercalcaemia — symptoms include nausea, vomiting, excessive thirst, polyuria, confusion, and in severe cases, cardiac arrhythmias and renal failure. It occurs with excessive supplementation (very high daily doses over many months) — not from sunlight exposure, which is self-limited. At the recommended 60,000 IU weekly for 8 weeks protocol, toxicity is very rare. Never give high-dose vitamin D to patients with sarcoidosis, granulomatous disease, or hypercalcaemia without specialist review.
⚠️All Vitamin D doses are in IU (International Units) of cholecalciferol (D3). Calcitriol (the active form, 1,25-OH Vit D) is dosed in micrograms and is prescribed only for specific conditions (CKD, hypoparathyroidism) — it is not a substitute for cholecalciferol supplementation. Verify against ICMR, IAP, and Endocrine Society guidelines.

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