Ceftiofur: veterinary dose and monograph

At a glance

Drug class

Antibiotic

Also known as

Excenel, Excede, Spectramast, Naxcel

Species with doses

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

General dose range

1.1–6.6 mg/kg IM q24h — check the species tables for the indication

Routes

IM, SC, IV, Intramammary

Last reviewed

1 October 2026

Indications

• Bovine respiratory disease (Mannheimia, Pasteurella, Histophilus somni)
• Bovine interdigital necrobacillosis (foot rot)
• Acute post-partum bovine metritis
• Bovine clinical mastitis (lactating, Spectramast LC)
• Bovine subclinical mastitis at dry-off (Spectramast DC)
• Swine bacterial respiratory disease

Ceftiofur 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

• UTI (ceftiofur sodium): Papich 5e: 2.2–4.4 mg/kg q24h SC. Plumb’s p.234 (Naxcel label): 2.2 mg/kg SC once daily for 5–14 days.
• Systemic / soft-tissue infection, sepsis (ceftiofur sodium): Plumb’s p.234 (Greene & Watson 1998): soft tissue 2.2 mg/kg q12h or 4.4 mg/kg q24h SC for 5–14 days; sepsis 4.4 mg/kg q12h SC for 2–5 days; neonatal septicaemia 2.5 mg/kg SC q12h for no more than 5 days (Davidson).

Cats

• UTI / soft-tissue infection (ceftiofur sodium): Plumb’s p.234 (Greene & Watson 1998): UTI 2.2 mg/kg SC once daily; systemic infections 2.2 mg/kg q12h or 4.4 mg/kg q24h; sepsis 4.4 mg/kg q12h for 2–5 days. Papich 5e: cat dose extrapolated from dogs.

Cattle

• BRD / interdigital necrobacillosis: Papich 5e and Plumb’s p.232 (Excenel RTU / Naxcel labels): 1.1–2.2 mg/kg IM or SC q24h for 3 days, with further doses on days 4 and 5 if needed; BRD alternative 2.2 mg/kg on days 1 and 3. Max 15 mL per site. Excenel RTU: 3-day slaughter withdrawal, no milk discard.
• Acute metritis: Papich 5e and Plumb’s p.232 (Excenel RTU label): postpartum metritis 2.2 mg/kg IM or SC once daily for 5 days; 3-day slaughter withdrawal, no milk discard.
• Neonatal salmonellosis: Plumb’s p.232 (Fecteau 2002): ceftiofur HCl 5 mg/kg IM once daily for 5 days. Extra-label dose — obtain a FARAD withdrawal (US extra-label cephalosporin restrictions apply).
• BRD — CRYSTALLINE FREE ACID depot (Excede), single dose: ⚠ FORMULATION-SPECIFIC: ceftiofur CRYSTALLINE FREE ACID only (Excede) — a long-acting depot, NOT interchangeable with ceftiofur sodium or hydrochloride. Papich 5th ed p.190: "6.6 mg/kg with a single SQ injection in the middle third of the posterior aspect of the ear." Giving the 1.1–2.2 mg/kg sodium/HCl dose as Excede under-doses by ~3×; giving 6.6 mg/kg of the sodium/HCl daily for 3 days over-doses by ~3×. Always check which salt is in the bottle.
• Lactating dairy clinical mastitis (Spectramast LC): Dosed per syringe, not per kg: 125 mg ceftiofur equivalents in a 10 mL syringe, one per affected quarter. Plumb's pp.231, 235: cattle must not be slaughtered for 2 days after the last treatment; milk taken during treatment and for 72 hours after must be discarded.
• Dry-cow subclinical mastitis (Spectramast DC): Dosed per syringe, not per kg: infuse ONE syringe (500 mg ceftiofur equivalents in 10 mL) into each affected quarter at the time of dry off. Labelled for S. aureus, Strep. dysgalactiae and Strep. uberis. Slaughter withdrawal 16 days; milk from cows that complete a 30-day dry period needs no discard, and calves born to treated cows need no withdrawal regardless of colostrum intake. Plumb's pp.231–232 (Spectramast DC package insert, Pfizer).

Horses

• Susceptible infection (ceftiofur sodium): Papich 5th ed p.194: horses 4.4 mg/kg q24h IM, or 2.2 mg/kg q12h IM, for as long as 10 days. Some gram-negative infections need the higher end; up to 11 mg/kg/day IM has been given. Horses are not food animals in India — no withdrawal applied.
• Foal septicaemia (ceftiofur sodium): Papich 5th ed p.194: foals 5 mg/kg q12h IV, or CRI 1 mg/kg/h IV.

Goats

• Susceptible infection: Papich 5e and Plumb’s p.234 (Naxcel label): sheep and goats 1.1–2.2 mg/kg IM (or SC) q24h for 3 days; days 4–5 if needed; use the high end in lactating does. Follow the label or FARAD for withdrawal.

Sheep

• Susceptible infection: Papich 5e and Plumb’s p.234 (Naxcel label): sheep and goats 1.1–2.2 mg/kg IM (or SC, Papich) q24h for 3 days; extra doses on days 4 and 5 if needed. Follow the label or FARAD for withdrawal.

Pigs

• Respiratory disease — CRYSTALLINE FREE ACID (Excede): Papich 5th ed p.190: 5.0 mg/kg IM in the postauricular region of the neck (crystalline free acid depot — single dose). Follow the product label for the slaughter withdrawal (crystalline free acid is a depot — much longer than the HCl/sodium forms).
• Swine respiratory disease: Papich 5e and Plumb’s p.232 (Excenel RTU / Naxcel labels): 3–5 mg/kg IM q24h for 3 days; max 15 mL per site. Excenel RTU: 4-day slaughter withdrawal; injection-site discolouration within 11 days may cause trim-out.

Buffalo

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

• BRD / interdigital necrobacillosis: Papich 5e and Plumb’s p.232 (Excenel RTU / Naxcel labels): 1.1–2.2 mg/kg IM or SC q24h for 3 days, with further doses on days 4 and 5 if needed; BRD alternative 2.2 mg/kg on days 1 and 3. Max 15 mL per site. Excenel RTU: 3-day slaughter withdrawal, no milk discard.
• Acute metritis: Papich 5e and Plumb’s p.232 (Excenel RTU label): postpartum metritis 2.2 mg/kg IM or SC once daily for 5 days; 3-day slaughter withdrawal, no milk discard.
• Neonatal salmonellosis: Plumb’s p.232 (Fecteau 2002): ceftiofur HCl 5 mg/kg IM once daily for 5 days. Extra-label dose — obtain a FARAD withdrawal (US extra-label cephalosporin restrictions apply).
• BRD — CRYSTALLINE FREE ACID depot (Excede), single dose: ⚠ FORMULATION-SPECIFIC: ceftiofur CRYSTALLINE FREE ACID only (Excede) — a long-acting depot, NOT interchangeable with ceftiofur sodium or hydrochloride. Papich 5th ed p.190: "6.6 mg/kg with a single SQ injection in the middle third of the posterior aspect of the ear." Giving the 1.1–2.2 mg/kg sodium/HCl dose as Excede under-doses by ~3×; giving 6.6 mg/kg of the sodium/HCl daily for 3 days over-doses by ~3×. Always check which salt is in the bottle.
• Lactating dairy clinical mastitis (Spectramast LC): Dosed per syringe, not per kg: 125 mg ceftiofur equivalents in a 10 mL syringe, one per affected quarter. Plumb's pp.231, 235: cattle must not be slaughtered for 2 days after the last treatment; milk taken during treatment and for 72 hours after must be discarded.
• Dry-cow subclinical mastitis (Spectramast DC): Dosed per syringe, not per kg: infuse ONE syringe (500 mg ceftiofur equivalents in 10 mL) into each affected quarter at the time of dry off. Labelled for S. aureus, Strep. dysgalactiae and Strep. uberis. Slaughter withdrawal 16 days; milk from cows that complete a 30-day dry period needs no discard, and calves born to treated cows need no withdrawal regardless of colostrum intake. Plumb's pp.231–232 (Spectramast DC package insert, Pfizer).

Contraindications

Hypersensitivity to cephalosporins (cross-reactivity with penicillins possible). Reduce dose in renal failure. Causes pain on IM injection in small animals.

Species-specific warnings

Cattle: Strict withdrawal periods — vary by formulation (Plumb's pp.231–232, 235): Naxcel / ceftiofur sodium 4 d meat, no milk discard; Excenel RTU 3 d meat, no milk discard; Spectramast LC 2 d meat / 72 h milk; Spectramast DC 16 d meat (no milk discard after a full 30-day dry period). Verify before extra-label use.

Horses: NOT approved for horses but used extra-label for metritis / respiratory. Causes pain on IM injection. Risk of antibiotic-associated colitis as with all broad-spectrum antibiotics in horses.

Pigs: Approved for swine respiratory disease. 4 d slaughter withdrawal. Use Excede for Swine 100 mg/mL formulation specifically.

Dogs: NOT a typical small-animal product — painful IM injection, no oral form. Cefovecin (Convenia) is preferred 3rd-gen ceph for dogs/cats.

Adverse effects

• Hypersensitivity (rare)
• Granulocytopenia, thrombocytopenia (rare)
• Diarrhoea
• Injection-site discoloration in food tissue (trim loss)
• Pain at IM injection

Drug interactions

• Aminoglycosides (gentamicin, neomycin): synergistic against Gram-negatives — do NOT mix in same syringe (physical inactivation)
• NSAIDs / loop diuretics (furosemide): additive nephrotoxicity in dehydrated or hypovolaemic animals
• Probenecid: prolongs ceftiofur half-life via blocked tubular secretion
• Other cephalosporins / penicillins: cross-reactivity for hypersensitivity (~10% co-allergy with penicillins)
• Warfarin / oral anticoagulants: may potentiate anticoagulant effect

Pregnancy and lactation

Generally considered safe in pregnant and lactating cattle, sows, and mares — extensively used in food-animal reproductive practice (post-partum metritis, retained placenta). Crosses placenta in low concentrations. No reported teratogenicity at label doses. Spectramast LC withdrawal: 72 h milk discard during lactation.

Monitoring

• Injection-site for swelling, sterile abscess — rotate sites
• Withdrawal periods strictly adhered to: 3 d slaughter / 0 h milk (Excenel BRD); 13 d slaughter / 72 h milk (Spectramast LC); 16 d slaughter (Spectramast DC dry-cow)
• Renal function (BUN, creatinine) if concurrent nephrotoxic drugs (NSAID, furosemide, aminoglycoside)
• Hypersensitivity signs in penicillin-allergic patients
• CBC if therapy >7 days — rare neutropenia / thrombocytopenia

Toxicity and overdose

Very wide therapeutic index. Acute toxicity rare even at 10× label dose. Chronic high-dose: granulocytopenia, thrombocytopenia (reversible). Injection-site reaction: discolouration of muscle (trim loss at slaughter), occasional sterile abscess. Hypersensitivity in penicillin-allergic patients (cross-reactivity ~10%).

Management: No specific antidote. Discontinue. Supportive: IV fluids, monitor renal function, anti-emetic. Anaphylaxis: epinephrine 0.01 mg/kg IM, diphenhydramine 2–4 mg/kg IM, IV fluids. Sterile abscess at injection site: drain if fluctuant, NSAID for pain.

Clinical pearls

• BRD: Excede 200 mg/mL SC base of ear at 6.6 mg/kg gives 7-day therapeutic levels — one-shot convenience
• Bovine metritis: post-partum within 14 days — 2.2 mg/kg IM q24h × 5 days reduces uterine clearance time
• Spectramast LC (lactating mastitis): 125 mg per quarter q24h × up to 8 milkings — only 72 h milk discard, lowest of major mastitis options
• Pain on IM injection in small animals — cephalosporin alternative (cefovecin Convenia) is preferred for dogs/cats
• Cross-reactivity with penicillin allergy is ~10% — caution in patients with known penicillin anaphylaxis
• Extra-label use in dairy cattle for non-FDA-approved indications carries strict FARAD-defined withdrawal

Mechanism of action

Third-generation cephalosporin (veterinary-only). Binds penicillin-binding proteins (PBPs) — inhibits peptidoglycan cross-linking in the bacterial cell wall, causing autolysis. Bactericidal, time-dependent. Active metabolite desfuroylceftiofur cysteine disulphide maintains tissue concentrations at infection sites for 4–7 days (long-acting Excede / Spectramast products). Stable to many extended-spectrum beta-lactamases. Good Gram-negative reach including respiratory and uterine pathogens; weaker on Gram-positives than 1st-gen cephs.

Formulations and products

• Excenel RTU (HCl) 50 mg/mL
• Excede 200 mg/mL (cattle)
• Excede for Swine 100 mg/mL
• Spectramast LC intramammary 125 mg per 10-mL syringe (lactating — Papich 5e p.162)
• Spectramast DC intramammary 500 mg per syringe (dry cow — Papich 5e p.162)
• Xyrofur 250 mg dry-powder vial (Intas) — reconstitute per label
• Xyrofur 500 mg dry-powder vial (Intas) — reconstitute per label
• Xyrofur 1 g dry-powder vial (Intas) — reconstitute per label
• Xyrofur Tazo 1.125 g dry-powder vial — ceftiofur 1 g + tazobactam 125 mg (Intas) — reconstitute per label
• Ceftiofur sodium powder (1 g & 4 g vials) reconstituted to 50 mg/mL (Naxcel / generic — Plumb’s p.235; Papich 5e p.164)
• Xyrofur (Intas (Neovet)) — 250 mg, Vial + WFI (parenteral)
• Xyrofur (Intas (Neovet)) — 500 mg, Vial + WFI (parenteral)
• Xyrofur (Intas (Neovet)) — 1 g, Vial + WFI (parenteral)
• Xyrofur Tazo (Intas (Neovet)) — Ceftiofur 1 g + Tazobactam 125 mg, Combination vial
• Ceftatime (Mankind Veticura) — Ceftiofur Sodium 1 g (anhydrous), Vial — reconstitute with 20 mL sterile water → 50 mg/mL
• Vetcefti-1 (Assure Biotech, Jagadhri (HR)) — 1 g ceftiofur sodium, Dry powder vial + 20 mL WFI ampoule
• Vetcefti-TZ 1.125 (Assure Biotech, Jagadhri (HR)) — Ceftiofur 1 g + Tazobactam 125 mg, Dry powder vial + 20 mL WFI ampoule

Storage

Reconstituted vial: refrigerate, use within 12 days (Excenel) / 5 days (Excede). Sterile suspension — shake well before use. Powder for reconstitution: store ≤25 °C. Intramammary syringes (Spectramast): store at controlled room temperature, do NOT freeze.

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

• Cefovecin
• Cefpodoxime proxetil
• Cefquinome
• Ceftazidime
• Ceftriaxone
• Cefuroxime
• Cephalexin
• Chloramphenicol

Frequently asked questions