Ceftriaxone: veterinary dose and monograph

At a glance

Drug class

Antibiotic

Also known as

Intacef, Intacef Tazo, Rocephin

Species with doses

Dogs, Cats, Cattle, Horses and Primates

General dose range

5–25 mg/kg IV q24h — check the species tables for the indication

Routes

IM, IV

Last reviewed

1 October 2026

Indications

• Severe systemic / Gram-negative bacterial infections
• Haemorrhagic septicaemia, pneumonia, bronchopneumonia
• Mastitis, metritis, pyometra, endometritis
• Actinobacillosis, osteoarthritis
• Peri-operative prophylaxis

Ceftriaxone 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

• Severe sepsis / pyometra / CNS infection: Plumb’s p.237 (Greene & Watson 1998): meningitis/borreliosis 15–50 mg/kg IV or IM q12h for 4–14 days; skin/genitourinary 25 mg/kg IM q24h for 7–14 days; peri-operative 25 mg/kg once; endocarditis 20 mg/kg IV q12h (DeFrancesco 2000). Give IV slowly over 2–4 min.

Cats

• Systemic infection: Plumb’s p.237 (Greene & Watson 1998): cats 25–50 mg/kg IV, IM or intraosseously q12h for systemic infections.

Cattle

• Mastitis / HS / metritis / pneumonia: IV or deep IM. WITHDRAWAL NOT ESTABLISHED: ceftriaxone is a human-label cephalosporin with no food-animal approval, and Plumb's carries no meat or milk withdrawal for it (the withdrawal figures on the neighbouring page belong to CEFTIOFUR, which is the food-animal cephalosporin). Indian catalogues nevertheless sell ceftriaxone widely for cattle and state no withdrawal. Treat every use in a food animal as extra-label with an undetermined withdrawal — contact FARAD, or use ceftiofur where a labelled withdrawal exists. No cattle dose appears in Papich 5e or Plumb’s; this regimen follows Indian veterinary product literature (Intacef). Dose source: Indian product labelling (5–10 mg/kg IM or IV once daily for 3–5 days) — neither Papich 5e nor Plumb’s gives a cattle ceftiofur-alternative dose for ceftriaxone. Prefer a cephalosporin licensed for cattle (ceftiofur, cefquinome).

Horses

• Susceptible infection (extra-label): Plumb’s p.237: 25–50 mg/kg IV or IM q12h — excellent CSF and bone penetration (Stewart 2008); 20 mg/kg IV q12h (Brumbaugh 1999).

Goats

• No reference dose for this species: The previous 10–15 mg/kg IM goat row had no source; neither Papich 5e nor Plumb’s gives a small-ruminant ceftriaxone dose, and no food-animal withdrawal exists.

Sheep

• No reference dose for this species: The previous 10–15 mg/kg IM sheep row had no source; neither Papich 5e nor Plumb’s gives a small-ruminant ceftriaxone dose, and no food-animal withdrawal exists.

Buffalo

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

• Mastitis / HS / metritis / pneumonia: IV or deep IM. WITHDRAWAL NOT ESTABLISHED: ceftriaxone is a human-label cephalosporin with no food-animal approval, and Plumb's carries no meat or milk withdrawal for it (the withdrawal figures on the neighbouring page belong to CEFTIOFUR, which is the food-animal cephalosporin). Indian catalogues nevertheless sell ceftriaxone widely for cattle and state no withdrawal. Treat every use in a food animal as extra-label with an undetermined withdrawal — contact FARAD, or use ceftiofur where a labelled withdrawal exists. No cattle dose appears in Papich 5e or Plumb’s; this regimen follows Indian veterinary product literature (Intacef). Dose source: Indian product labelling (5–10 mg/kg IM or IV once daily for 3–5 days) — neither Papich 5e nor Plumb’s gives a cattle ceftiofur-alternative dose for ceftriaxone. Prefer a cephalosporin licensed for cattle (ceftiofur, cefquinome).

Primates

• Susceptible infection (monkeys, siamangs): Carpenter Exotic Animal Formulary 6th ed, Table 13-1 (p.681): monkeys/siamangs 25–100 mg/kg IM or IV q12h; chimpanzees 50–100 mg/kg IM q12–24h.

Contraindications

Cephalosporin hypersensitivity (cross-reactivity with penicillins). Use cautiously in renal failure (reduce dose). Do NOT mix with calcium-containing IV solutions — precipitate / fatal lung & kidney emboli. Not approved for food animals in many jurisdictions — confirm withdrawal locally.

Species-specific warnings

Rabbits: Avoid in rabbits — cephalosporins can cause fatal clostridial enterotoxaemia.

Adverse effects

• GI upset (vomiting, diarrhoea)
• Local injection-site pain (IM)
• Hypersensitivity / urticaria (rare)
• Biliary pseudolithiasis (high doses, dogs)
• Calcium-ceftriaxone precipitation in IV lines

Drug interactions

• Aminoglycosides (gentamicin): synergistic against many Gram-negatives — but do NOT mix in same syringe (physical inactivation)
• Loop diuretics (furosemide) / nephrotoxins: additive nephrotoxicity in dehydrated patients
• Calcium-containing IV solutions: NEVER co-infuse with ceftriaxone in same line — precipitation can cause fatal embolism (esp. in neonates)
• Penicillins: cross-reactivity for hypersensitivity (~10% co-allergy)
• Warfarin / oral anticoagulants: may potentiate anticoagulation
• Probenecid: prolongs ceftriaxone half-life

Pregnancy and lactation

Generally considered safe in pregnancy at therapeutic doses. Crosses placenta in low concentrations. Excreted in milk. FDA Category B (human). Used in pregnant queens, bitches, mares for severe infections.

Monitoring

• Renal function (BUN, creatinine) baseline and on prolonged courses
• CBC if treatment exceeds 7 days — rare neutropenia / thrombocytopenia
• Hypersensitivity signs especially first dose
• Injection-site for pain / swelling (deep IM technique)
• Withdrawal periods (cattle extra-label): cross-reference with FARAD
• NEVER mix with Ca²⁺-containing IV solutions (LRS, calcium gluconate)

Toxicity and overdose

Wide therapeutic margin. Acute toxicity rare. Chronic high-dose: granulocytopenia, thrombocytopenia (reversible). Biliary sludge / pseudolithiasis with prolonged high-dose use (calcium chelation in bile). Hypersensitivity (urticaria, anaphylaxis). NEONATES: NEVER co-administer with calcium-containing solutions — fatal calcium-ceftriaxone precipitate in lungs / kidneys.

Management: No specific antidote. Supportive: IV fluids, anti-emetic. Anaphylaxis: epinephrine 0.01 mg/kg IM, diphenhydramine, corticosteroid. Hemodialysis NOT effective (highly protein-bound). Biliary sludge: usually self-resolves on discontinuation.

Clinical pearls

• Canine severe sepsis / CNS infection: 15–25 mg/kg IV slow over 2–4 min q12–24h
• Canine pyometra (pre-/post-op coverage): 25 mg/kg IV q12h
• Bovine respiratory disease, mastitis, metritis: 5–10 mg/kg IM q24h × 3–5 days — Intacef widely used in Indian dairy
• Goats / sheep: 10–15 mg/kg IM q24h × 3–5 days
• Equine: 25–50 mg/kg IV q12–24h for severe Gram-negative sepsis (extra-label, foals especially)
• Intacef Tazo (with tazobactam) extends spectrum to ESBL-producing organisms — useful for refractory UTI / sepsis
• NEVER co-infuse with calcium-containing fluids (LRS) — fatal precipitate in lungs/kidneys, especially in neonates
• Reconstituted solution stable 24 h at RT — convenient for once-daily clinic use

Mechanism of action

Third-generation cephalosporin (human-medicine origin, extra-label in vet practice). Binds penicillin-binding proteins (PBPs) — inhibits transpeptidase cross-linking of peptidoglycan. Bactericidal, time-dependent killing. Extended-spectrum: enhanced Gram-negative coverage (E. coli, Klebsiella, Proteus, Enterobacter, Pasteurella), weaker on Gram-positives than 1st-gen. Stable to most beta-lactamases (further stabilised by tazobactam combination — Intacef Tazo). Excellent CSF penetration in inflamed meninges. Long half-life (~6 h) allows q24h dosing in most species.

Formulations and products

• Intacef dry-powder vials 250 mg / 500 mg / 1 g / 2 g / 3 g / 4 g / 5 g (Intas) — reconstitute per label
• Intacef Tazo dry-powder vials 562.5 mg / 2.25 g / 3.375 g / 4.5 g / 5.625 g (Intas) — reconstitute per label
• Powder reconstituted to ≈100 mg/mL (Plumb’s p.237 — diluent volume per vial label)
• Powder reconstituted to 250 mg/mL (Plumb’s p.237 — diluent volume per vial label)
• Intacef (Intas (Neovet)) — 250 mg, Vial + WFI + sterile syringe
• Intacef (Intas (Neovet)) — 500 mg, Vial + WFI
• Intacef (Intas (Neovet)) — 1 g, Vial + WFI
• Intacef (Intas (Neovet)) — 2 g, Vial + WFI
• Intacef (Intas (Neovet)) — 3 g / 4 g / 5 g, Vial + WFI (large animal pack)
• Intacef Tazo (Intas (Neovet)) — Ceftriaxone 500 + Tazobactam 62.5 mg, Vial + WFI
• Intacef Tazo (Intas (Neovet)) — Ceftriaxone 4 g + Tazobactam 500 mg, Large-animal vial
• Ceftiforce-500 (Pet Mankind (Mankind Pharma)) — Ceftriaxone 500 mg, Vial
• Ceftiforce-Tazo (Pet Mankind (Mankind Pharma)) — Ceftriaxone 500 + Tazobactam 62.5 mg, Vial
• Seftravet-3 (Assure Biotech, Jagadhri (HR)) — 3 g ceftriaxone, Dry powder vial + 20 mL WFI ampoule
• Monocef — 250 / 500 / 1000 / 2000 mg, Vial (human-label)
• Rocephin — 250 / 500 / 1000 / 2000 mg, Vial (human-label)

Storage

Powder vials: 15–25 °C, protected from light. Reconstituted solution: use within 24 h at room temp or 48 h refrigerated. Multidose vial: discard 28 days after broaching. Tazobactam combination (Intacef Tazo): same conditions.

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 antibiotics

• Cefpodoxime proxetil
• Cefquinome
• Ceftazidime
• Ceftiofur
• Cefuroxime
• Cephalexin
• Chloramphenicol
• Ciprofloxacin

Frequently asked questions