Ceftiofur HCl
Ceftiofur hydrochloride
Also known as: Excenel RTU · Spectramast DC · Spectramast LC · Naxcel (Sodium salt variant) · Cefenil · U-64279A · ceftiofuri hydrochloridium · Ceftiofurum · Ceftiofur sodium
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Susceptible urinary tract infections | 2.2 mg/kg | SC | q24h | Not specified | 🌍 EU |
| Sepsis/bacteraemia | 4.4 mg/kg | SC | q24h | Not specified | 🌍 EU |
- Susceptible urinary tract infections: Authorized for use in dogs in other countries where the main indication is UTI treatment.
- Sepsis/bacteraemia: Higher (double) dose indicated to treat sepsis/bacteraemia.
Cattle
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Bovine respiratory disease and acute bovine interdigital necrobacillosis | 1.1 to 2.2 mg/kg | IM/SC | q24h | 3 days (up to 5 days if needed) | 🌎 NA |
| Bovine respiratory disease (BRD) only | 2.2 mg/kg | IM/SC | q48h | Days 1 and 3 | 🌎 NA |
| Acute post-partum metritis | 2.2 mg/kg | IM/SC | q24h | 5 consecutive days | 🌎 NA |
| Neonatal salmonellosis | 5 mg/kg | IM | q24h | 5 days | 🌎 NA |
| Subclinical mastitis at time of dry off | Infuse one syringe (500 mg) | Intramammary | Once | At dry off | 🌎 NA |
| Clinical mastitis in lactating dairy cattle | Infuse one syringe (125 mg) | Intramammary | q24h | 2 days (up to 8 consecutive days for extended therapy) | 🌎 NA |
- Bovine respiratory disease and acute bovine interdigital necrobacillosis: Do not inject more than 15 mL per injection site.
- Bovine respiratory disease (BRD) only: Do not inject more than 15 mL per injection site.
- Acute post-partum metritis: Do not inject more than 15 mL per injection site.
- Subclinical mastitis at time of dry off: Infuse into each affected quarter.
- Clinical mastitis in lactating dairy cattle: Infuse into each affected quarter.
Swine
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Bacterial respiratory disease | 3 to 5 mg/kg | IM | q24h | 3 consecutive days | 🌎 NA |
- Bacterial respiratory disease: 1 mL of sterile suspension per 22 to 37 lb body weight.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Ceftiofur HCl is a veterinary-only, third-generation cephalosporin antibiotic. It is primarily utilized in large animal medicine (particularly swine and cattle) for the treatment of bacterial respiratory diseases, foot rot, acute metritis, and mastitis.
Key characteristics include:
- Broad-Spectrum Activity: Effective against a wide variety of Gram-positive and Gram-negative pathogens, including Pasteurella, Streptococcus, Staphylococcus, Salmonella, and E. coli.
- Active Metabolite: Rapidly converts to desfuroylceftiofur, which is equally potent to the parent drug.
- Clinical Pearl: Certain formulations of ceftiofur (like Excenel RTU) offer a zero-day milk discard time in lactating dairy cattle, making it highly advantageous for dairy operations, though strict slaughter withdrawal times still apply.
Mechanism of action
Ceftiofur is a time-dependent, bactericidal antibiotic.
- Mechanism: It binds to penicillin-binding proteins (PBPs) located inside the bacterial cell wall → inhibits the third and final stage of bacterial cell wall synthesis → leads to weakened cell walls, cell lysis, and bacterial death.
- Metabolism Pathway: Parent ceftiofur is rapidly cleaved into furoic acid and desfuroylceftiofur (the primary active metabolite).
- Reservoir Effect: The active metabolite is highly protein-bound, which creates a 'reservoir effect' that maintains active, therapeutic drug concentrations at the site of infection for extended periods.
Safety & warnings
Contraindications
- Patients with a documented history of hypersensitivity to cephalosporins
- Use with caution in patients hypersensitive to other beta-lactam antibiotics (e.g., penicillins, carbapenems) due to potential cross-reactivity
Adverse effects
- Pain on IM injection (especially in small animals)
- Hypersensitivity reactions (rashes, fever, eosinophilia, lymphadenopathy, anaphylaxis)
- Gastrointestinal distress / diarrhea
- Granulocytopenia (rare)
- Thrombocytopenia (rare)
- Injection site discoloration
Precautions
Warning: Hypersensitivity reactions can occur. Cross-reactivity with penicillins is possible.
- Tissue Discoloration: IM or SC injections can cause injection site discoloration, resulting in trim-out of edible tissues at slaughter (persisting up to 11 days in the neck, or >28 days in the rear leg of cattle).
- Withdrawal Times: Strict adherence to slaughter and milk withdrawal times is legally required and varies significantly by specific product and species.
- Renal Impairment: Patients in renal failure may require dosage adjustments due to decreased clearance.
- Laboratory Interference: May cause false-positive urine glucose tests (cupric sulfate method), falsely elevated creatinine (Jaffe reaction), and false-positive direct Coombs' tests.
Drug interactions
Potential for additive nephrotoxicity. In vitro studies show synergistic antibacterial activity, but they must NOT be mixed together in the same syringe or fluid line.
Competitively blocks the tubular secretion of most cephalosporins, thereby increasing serum levels and prolonging serum half-lives.
Synergistic antibacterial effect, but should not be mixed in the same syringe due to chemical incompatibility.
Increased risk of nephrotoxicity.
Increased risk of nephrotoxicity.
Monitoring
- Clinical efficacy and resolution of infection
- Weekly CBC monitoring (if used off-label in small animals)
- Renal function parameters in patients with pre-existing renal impairment
- Injection site reactions
Pharmacokinetics
Absorption
Rapidly absorbed following intramuscular (IM) or subcutaneous (SC) administration.
Distribution
Volume of distribution in cattle is approximately 0.3 L/kg. Protein binding creates a 'reservoir effect' at the site of infection. In swine, highest tissue concentrations are found in the kidneys, followed by lungs, liver, and muscle.
Metabolism
Rapidly metabolized to desfuroylceftiofur, the primary active metabolite, which has equivalent potency to the parent compound.
Elimination
Eliminated primarily via the kidneys. Elimination half-life in cattle is approximately 8-12 hours. Elimination kinetics in milk can vary based on milk production volume; cows producing smaller volumes may have prolonged withdrawal times.
Overdose
Cephalosporin overdoses are generally well-tolerated and unlikely to cause significant problems other than gastrointestinal distress. However, extreme overdoses could theoretically induce hypersensitivity or hematologic abnormalities.
Important: Use of dosages in excess of those labeled or via unapproved routes may cause violative tissue or milk residues. Contact FARAD for assistance in determining appropriate withdrawal times if an overdose occurs in food-producing animals.
Available products
Formulations
- Injectable sterile suspension (ready-to-use)
- Intramammary infusion syringe (dry cow)
- Intramammary infusion syringe (lactating cow)
Veterinary
- Ceftiofur HCl Sterile Suspension for injection: 50 mg/mL in 100 mL vials (Excenel RTU®)
- Ceftiofur HCl Sterile Suspension for Intramammary Infusion in Dry Cows: 500 mg per 10 mL syringe (Spectramast® DC)
- Ceftiofur HCl Sterile Suspension for Intramammary Infusion in Lactating Cows: 125 mg per 10 mL syringe (Spectramast® LC)
Regulatory status
POM-V. Only licensed for use in large animals in the UK/EU; use in dogs is off-label (cascade).
POM-V. Only licensed for use in large animals; use in dogs is off-label.
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store ready-to-use injectable products and intramammary syringes at controlled room temperature 20 to 25 °C (68 to 77 °F). Shake injectable suspensions well before using. Protect from freezing. Protect intramammary syringes from light and store in carton until used.
Client information
Note: This medication is primarily prescribed for livestock (cattle and swine).
- Administration: Administer exactly as directed by your veterinarian. Complete the entire course of treatment even if the animal appears to have recovered, to prevent antibiotic resistance.
- Food Animal Safety: Strict adherence to slaughter and milk withdrawal times is legally required to prevent drug residues in the human food supply. Withdrawal times vary depending on the specific product used (e.g., Excenel RTU vs. Spectramast).
- Side Effects: Monitor for signs of allergic reactions (such as hives, swelling, or difficulty breathing) and diarrhea.
- Injection Sites: Be aware that injections may cause temporary pain and tissue discoloration at the injection site.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.