B-Complex Injection (B1 + B6 + B12): veterinary dose and monograph

At a glance

Drug class

Veterinary drug

Also known as

Tribivet, B-Complex Vet, Tribivet B

Species with doses

Dogs, Cats, Cattle, Horses, Goats, Sheep and Pigs

Routes

IM, SC

Last reviewed

1 October 2026

Indications

• Anorexia / inappetence — large and small animals
• Recovery from chronic disease
• Adjunct in ketosis / metabolic disorders
• Post-deworming / post-antibiotic recovery
• B12 deficiency in cobalt-deficient regions
• Polioencephalomalacia (PEM) in ruminants — high-dose thiamine

B-Complex Injection (B1 + B6 + B12) 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.

Dogs

• Supportive / appetite: Catalogue: 0.5–2 mL IM (dose by size).

Cats

• B12 deficiency / chronic GI: For chronic enteropathy in cats — 250 µg cyanocobalamin SC weekly is the Plumb's standard. Tribivet 0.5 mL provides similar B12 content.

Cattle

• General supportive / appetite: Tribivet catalogue: 5–10 mL IV or IM in cattle / buffalo / horse. Repeat daily for 3–7 days.
• Polioencephalomalacia (high-dose thiamine): This combination product is NOT adequate for polioencephalomalacia — give dedicated thiamine at the PEM dose (see the thiamine monograph). The catalogue volume of this product supplies far too little thiamine for PEM.

Horses

• Supportive / appetite: Catalogue: 5–10 mL IM.

Goats

• Supportive: Catalogue: 1–2 mL IM in sheep / goat / swine.

Sheep

• Supportive: Catalogue: 1–2 mL IM.

Pigs

• Supportive: Catalogue: 1–2 mL IM.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

• General supportive / appetite: Tribivet catalogue: 5–10 mL IV or IM in cattle / buffalo / horse. Repeat daily for 3–7 days.
• Polioencephalomalacia (high-dose thiamine): This combination product is NOT adequate for polioencephalomalacia — give dedicated thiamine at the PEM dose (see the thiamine monograph). The catalogue volume of this product supplies far too little thiamine for PEM.

Contraindications

Hypersensitivity (very rare). Caution with IV in animals with low BP — give slowly.

Species-specific warnings

Cattle: For PEM use dedicated high-dose thiamine; Tribivet is supportive but not the primary drug.

Cats: Cat chronic enteropathy benefits from weekly B12 — Plumb's standard.

Adverse effects

• Pain on IM injection (especially large volume)
• Hypersensitivity (rare)

Pregnancy and lactation

Safe — supportive therapy.

Monitoring

• Clinical appetite / energy response
• Body condition trend on prolonged courses

Clinical pearls

• Cat with chronic enteropathy and low cobalamin: 250 µg SC weekly × 6 weeks then monthly is the Plumb's standard — Tribivet 0.5 mL covers this
• Bovine PEM emergency: 10 mg/kg thiamine IM q6h for 24 h — Tribivet alone is INSUFFICIENT (only 50 mg/mL thiamine); use dedicated thiamine HCl injection
• Post-antibiotic recovery in calves: 2–5 mL Tribivet IM daily × 5 days restores appetite faster than nothing
• Pair Tribivet with multivitamin AD3E for full vitamin coverage in chronic / scouring patients

Mechanism of action

B1 (Thiamine) — cofactor for pyruvate dehydrogenase and α-ketoglutarate dehydrogenase; central to glucose metabolism and nerve function. B6 (Pyridoxine) — cofactor for transaminases and decarboxylases in amino acid and neurotransmitter synthesis. B12 (Cyanocobalamin) — cofactor for methylmalonyl-CoA mutase and methionine synthase; essential for haematopoiesis and nerve myelination.

Formulations and products

• Tribivet — Thiamine (B1) 50 mg + Pyridoxine (B6) 50 mg + Cyanocobalamin (B12) 500 µg per mL (Intas)
• Tribivet (Intas (Neovet)) — B1 50 mg + B6 50 mg + B12 500 µg per mL, IV / IM injection
• Sure-Liv-B (Assure Biotech, Jagadhri (HR)) — Thiamine 10 mg + Riboflavin Na phosphate 3 mg + Nicotinamide 100 mg + Cyanocobalamin 10 mcg + Pyridoxine 5 mg + Choline chloride 25 mg + Liver extract 0.66 mL per mL, Injection - IM or IV
• Sure-Multi Vet (Assure Biotech, Jagadhri (HR)) — Thiamine (B1) 50 mg + Pyridoxine (B6) 50 mg + Cyanocobalamin (B12) 500 mcg per mL, Injection - IM or IV

Storage

15–25 °C, protect from light.

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.

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Frequently asked questions