Cefixime
Cefixime trihydrate
Also known as: Suprax · cefiximum · CL-284635 · FK-027 · FR17027
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 |
|---|---|---|---|---|---|
| Infectious endocarditis | 10 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| UTI | 5 mg/kg PO once to twice daily | PO | q12h or q24h | 7-14 days | 🌎 NA |
| Respiratory, systemic infections | 12.5 mg/kg PO q12h | PO | q12h | 7-14 days | 🌎 NA |
| Susceptible infections | 5 mg/kg PO once to twice a day | PO | q12h or q24h | — | 🌎 NA |
- Infectious endocarditis: Use when documented resistance against or other contraindications for fluoroquinolones and aminoglycosides exist.
- Respiratory, systemic infections: Duration of treatment dependent on chronicity of infection.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Susceptible infections | 5-12.5 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Cefixime is an oral 3rd-generation cephalosporin antibiotic used in veterinary medicine primarily for susceptible gram-negative infections.
- Spectrum of Activity: Highly effective against many Enterobacteriaceae (e.g., Escherichia coli, Proteus, Klebsiella) and some gram-positive organisms like Streptococcus.
- Limitations: It is generally not effective against Pseudomonas aeruginosa, Enterococcus, Staphylococcus, Bordetella, or anaerobes.
- Clinical Utility: Its use is typically reserved for systemic or urinary tract infections where oral treatment is desired, and when first-line agents (like fluoroquinolones or other cephalosporins) are contraindicated or ineffective.
Clinical Pearl: Because bacterial sensitivity to 3rd-generation cephalosporins is highly variable, culture and susceptibility testing using cefixime-specific disks or dilutions is strongly recommended before initiating therapy.
Mechanism of action
Cefixime is a bactericidal antibiotic that works by inhibiting bacterial cell wall synthesis.
- Binds to specific Penicillin-Binding Proteins (PBPs) located inside the bacterial cell wall.
- Inhibition of transpeptidation → prevents cross-linking of peptidoglycan chains.
- Activation of autolysins → leads to bacterial cell wall lysis and death.
It is relatively resistant to hydrolysis by many bacterial beta-lactamases, allowing it to remain effective against certain resistant gram-negative strains.
Safety & warnings
Contraindications
- Hypersensitivity to cefixime or other cephalosporins
Adverse effects
- Gastrointestinal distress (vomiting, diarrhea)
- Hypersensitivity reactions (urticaria, pruritus, fever)
Precautions
Important Precautions:
- Renal Impairment: Because cefixime is primarily excreted by the kidneys, dosages and/or dosage frequency may need to be adjusted in patients with significantly diminished renal function.
- Cross-Reactivity: Use with caution in patients allergic to penicillins due to the potential for cross-reactivity.
- Neurologic Conditions: Use with caution in patients with seizure disorders, as high levels of beta-lactams can lower the seizure threshold.
- Laboratory Interference: May cause false-positive urine glucose determinations when using cupric sulfate solution (e.g., Clinitest) and false-positive urinary ketones with nitroprusside tests.
Drug interactions
Competitively blocks the tubular secretion of most cephalosporins, thereby increasing serum levels and serum half-lives.
May displace cefixime from plasma protein binding sites; clinical significance is unclear.
Monitoring
- Clinical efficacy (resolution of infection)
- Adverse effects (GI signs, allergic reactions)
- Renal function (in patients with pre-existing renal disease)
Pharmacokinetics
Half-life
Absorption
Relatively rapidly absorbed after oral administration. Bioavailability in the dog is about 50%. Food may impede the rate, but not the extent, of absorption. The suspension may have a higher bioavailability than tablets.
Distribution
Fairly highly bound to plasma proteins in the dog (about 90%). It is unknown if the drug penetrates into the CSF.
Metabolism
Not extensively metabolized; primarily eliminated unchanged.
Elimination
Eliminated by both renal and non-renal means. Serum half-lives are prolonged in patients with decreased renal function.
Overdose
Cephalosporin overdoses are generally unlikely to cause significant problems.
- Expected Signs: Massive overdoses may result in gastrointestinal distress (vomiting, diarrhea) or hypersensitivity reactions.
- Management: Treatment is largely supportive and symptomatic. Emptying the stomach may be considered for massive, recent ingestions.
Available products
Formulations
- Powder for oral suspension
Human-labeled
- Cefixime Powder for Oral Suspension: 100 mg/5 mL in 50 mL, 75 mL & 100 mL
- Cefixime Powder for Oral Suspension: 200 mg/5 mL in 25 mL, 37.5 mL, 50 mL, 75 mL & 100 mL
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Cefixime powder for suspension should be stored at room temperature in tight containers. After reconstitution of the oral suspension, refrigeration is not required, but it should be discarded after 14 days whether refrigerated or not.
Client information
Cefixime is an antibiotic used to treat specific bacterial infections in your pet.
- Administration: Can be given with or without food. If your pet vomits after receiving the medication on an empty stomach, try giving future doses with a small treat or meal.
- Completion of Therapy: Give the medication exactly as directed for as long as your veterinarian recommends, even if your pet appears well. Stopping early can lead to resistant infections.
- Storage: The liquid suspension can be kept at room temperature and does not require refrigeration. Discard any unused liquid after 14 days.
- Side Effects: Watch for vomiting, diarrhea, or signs of an allergic reaction (such as hives, itching, or facial swelling). Contact your veterinarian if these occur.
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.