Oral Calcium / Phosphorus Bolus (Calcimust): veterinary dose and monograph

At a glance

Drug class

Veterinary drug

Also known as

Calcimust, Calcimust Bolus, Calcium-phosphorus oral bolus

Species with doses

Cattle and Buffalo

Routes

PO

Last reviewed

1 October 2026

Indications

• Periparturient calcium prophylaxis (pre- and post-calving cattle / buffalo)
• Milk fever relapse prevention (after IV calcium)
• Subclinical hypocalcaemia / inappetence post-calving
• Phosphorus supplementation in high-production dairy

Oral Calcium / Phosphorus Bolus (Calcimust) dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Cattle

• Milk fever prophylaxis (gel protocol): Catalogue: Bottle 1 — 1–24 h before parturition; Bottle 2 — immediately after parturition; Bottle 3 — 12 h post; Bottle 4 — 24 h post. Each 300 g bottle = 1 oral dose.
• Milk fever relapse prevention: Catalogue: After successful IV calcium, give Bottle 1 immediately, Bottle 2 at 24 h, Bottle 3 at 48 h.
• Daily calcium supplementation (bolus): Catalogue: 1 bolus PO BID morning and evening. For teat-crack prevention: start 2 weeks before calving.

Goats

• No reference dose for this species: The previous row extrapolated ‘half the cow bolus dose’ with no source. The product is labelled for cattle and buffalo; neither Papich 5e nor Plumb’s covers it.

Buffalo

• Periparturient milk-fever prophylaxis / relapse prevention: Mankind Calcimust labels buffalo with cattle (same protocol). Buffalo are highly milk-fever-prone at calving: gel Bottle 1 pre-calving → 2 post-calving → 3 at 12 h → 4 at 24 h; or 1 bolus PO BID. Recumbent clinical milk fever still needs IV calcium borogluconate FIRST.

Contraindications

Severe hypercalcaemia. Acute milk fever with recumbency requires IV calcium first — oral products alone are inadequate. Do not over-supplement in dry-period cows on DCAD diets.

Species-specific warnings

Cattle: Use as ADJUNCT to IV calcium borogluconate in recumbent milk fever, not as primary therapy. Prophylaxis use 12 h pre-calving is high-value in high-risk cows.

Adverse effects

• Hypercalcaemia (over-supplementation) — rare
• Soft-stool with prolonged use (high phosphorus load)

Pregnancy and lactation

Safe in pregnant cows / buffaloes at recommended doses — primary use is prophylaxis in the periparturient window.

Monitoring

• Clinical milk fever signs — calcium gel is supportive, not curative for recumbent cows
• Serum total calcium ideally; in field practice, clinical response (rises, eats, milks) is the marker
• Body condition score and recurrence pattern across lactations — habitual relapsers benefit from prophylactic gel protocol

Clinical pearls

• High-risk cow (previous milk fever, ≥4th lactation, high producer): give Bottle 1 of Calcimust Gel 12 h pre-calving — single biggest prevention win in Indian dairy
• Post-IV calcium relapse prevention: gel immediately + 24 h + 48 h prevents most relapses (~70% of cows that relapse do so within 48 h)
• Bolus form for daily pre-calving supplementation 2 weeks before calving: maintains calcium reserves and reduces teat oedema / cracks
• Calcium gel is NOT a substitute for IV calcium in a down cow — give IV first, then oral supportive
• Always verify cow can swallow before drenching gel — recumbent / depressed cows are aspiration risks

Mechanism of action

Calcium carbonate / tribasic calcium phosphate dissolves in the rumen acid environment, releasing ionised Ca²⁺ for intestinal absorption. Vitamin D3 (cholecalciferol) is bio-converted to 1,25-dihydroxy-vitamin D in the kidney, upregulating intestinal calcium absorption and bone mobilisation. The herbal / mineral co-factors in the proprietary formula contribute to gut motility and absorption efficacy. Oral calcium is best used pre-calving to prime the calcium-handling pathway and post-IV-calcium to maintain serum levels above the relapse threshold.

Formulations and products

• Calcimust Bolus (Mankind) — Calcium 2 g + Phosphorus 1 g + Vit D3 20 000 IU + Vit A 50 000 IU per bolus
• Calcimust Gel (Mankind) — Calcium 19.8 g + Phosphorus 10.2 g + Vit D3 96 000 IU per 300 g bottle
• Calcimust Bolus (Mankind Veticura) — Calcium 2 g + Phosphorus 1 g + Vit D3 20 000 IU + Vit A 50 000 IU + Vit E 100 mg + B12 100 µg per bolus, Oral bolus
• Calcimust Gel (Mankind Veticura) — Calcium 19.8 g + Phosphorus 10.2 g + Vit D3 96 000 IU + Vit B12 1200 µg per 300 g bottle, Oral gel — drench bottle
• Microcal 4G (Micro Animal Health Care (Micro Labs group), Bengaluru) — Calcium 4000 mg + Phosphorus 2500 mg + Vitamin D3 16000 IU + Vitamin B12 200 mcg + Carbohydrate 28000 mg per 100 mL, Oral calcium suspension
• Calsure-Gold Advance Gel (Assure Biotech, Jagadhri (HR)) — Ionic calcium 10000 mg + Phosphorus 5000 mg + Vitamin D3 32000 IU per 100 g, with Pueraria mirifica and herbal extracts, Oral calcium gel
• Lactica HG (VetMed Pvt Ltd, Kolkata) — Calcium 3.256 g + Phosphorus 1.67 g + Vitamin D3 18000 IU + Vitamin B12 200 mcg per 100 mL, with herbal galactagogue, Oral calcium syrup

Storage

Tablets / boluses: 15–25 °C, dry, protected from light. Gel bottles: 15–25 °C — shake before use.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Other hormones, emergency drugs, supplements and other drugs

• Nandrolone Decanoate
• Neostigmine
• Oclacitinib
• Octreotide
• Oral Iron + B12 + Folic Acid (Feritas / Ferikind)
• Oxytocin
• Penicillamine (D-Penicillamine)
• Pentoxifylline

Frequently asked questions