Quick Facts
| CAS Number | 93106-60-6 |
|---|---|
| Molecular Formula | C19H22FN3O3 |
| Molecular Weight | 359.401 |
| Pharmacopoeia | EP, CPV |
| Packaging | 25 KG/DRUM |
Product Overview
Enrofloxacin was discovered and developed by Bayer AG in the early 1980s and launched in the late 1980s under the brand name Baytril. It was the first fluoroquinolone antibiotic developed specifically for veterinary use — a landmark moment in veterinary pharmaceutical history. Bayer's scientists took the then-new fluoroquinolone scaffold (pioneered with norfloxacin and ciprofloxacin for human medicine) and optimized it for veterinary species. The compound was patented (US patent 4,528,287) and quickly became the most commercially successful veterinary antibiotic of its era. Even today, more than 35 years after its introduction, enrofloxacin remains the most widely prescribed veterinary fluoroquinolone worldwide.
Enrofloxacin exerts its bactericidal effect through a dual-target mechanism: it inhibits both bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, enzymes essential for DNA replication, transcription, and repair. This dual-targeting is clinically significant because it reduces the probability of single-step resistance mutations — a bacterium must acquire mutations in both target enzymes to become resistant, a much rarer event than single-target resistance. Enrofloxacin demonstrates concentration-dependent killing, meaning higher peak concentrations produce more rapid and complete bacterial eradication. This pharmacodynamic property guides both dosing regimens and the clinical principle of using the highest safe dose rather than the lowest effective dose.
A distinctive feature of enrofloxacin is its metabolic conversion: in the liver, approximately 30-50% of administered enrofloxacin is de-ethylated to ciprofloxacin, its equally active fluoroquinolone metabolite. Both compounds circulate simultaneously and contribute to the overall therapeutic effect. This dual-active-moiety profile — enrofloxacin providing sustained levels and its metabolite ciprofloxacin adding additional antimicrobial pressure — contributes to enrofloxacin's clinical reliability across a broad range of infections. In essence, the animal receives the benefit of two fluoroquinolones from a single administered compound. The combined enrofloxacin + ciprofloxacin concentration is the marker residue used in MRL assessments and withdrawal period determinations.
As of mid-2026, the global enrofloxacin API market is one of the largest veterinary antibiotic segments by volume, driven by massive use in poultry and swine production across Asia, Latin America, and Africa. However, enrofloxacin's status as a WHO-listed Critically Important Antimicrobial means its regulatory landscape is evolving — the US FDA prohibited extra-label use in poultry in 2005, and the EU has tightened fluoroquinolone prescribing requirements. These restrictions are creating a two-tier market: regulated markets with restricted fluoroquinolone access, and emerging markets where enrofloxacin remains a workhorse antibiotic. China dominates global API production. KingWish supplies GMP-certified enrofloxacin meeting EP and CPV monographs, with full impurity profile data supporting regulatory filings in both established and emerging markets.
Quality Specifications
| Purity (HPLC) | ≥ 98.5%, per EP/CPV monograph |
|---|---|
| Related Substances | Ciprofloxacin (impurity) ≤ 0.2%; decarboxylated derivative ≤ 0.1%; any individual impurity ≤ 0.2%; total impurities ≤ 0.5% |
| Water Content (Karl Fischer) | ≤ 1.0% |
| Residual Solvents | DMF ≤ 880 ppm; acetonitrile ≤ 410 ppm; per ICH Q3C |
| Heavy Metals | ≤ 20 ppm |
| GMP Status | Manufactured under ICH Q7 GMP conditions |
| Regulatory Support | EP/CPV monograph compliance; documentation available for customer DMF/MAA submissions |
Veterinary Applications
Oral Solution (Poultry & Swine)
Enrofloxacin 10% oral solution. Poultry: 50-100 ppm in drinking water (50-100 mg/L) for 3-5 days. Swine: 2.5-5.0 mg/kg BW via drinking water. High oral bioavailability (>80% in most species).
Injectable (Cattle & Companion Animals)
Enrofloxacin 5% or 10% injectable. Cattle: 2.5-5.0 mg/kg IM/SC once daily for BRD. Dogs/Cats: 2.5-5.0 mg/kg SC/IM or oral tablets. Excellent intracellular penetration for deep-seated infections.
Therapeutic Areas
- Poultry: Colibacillosis, mycoplasmosis (CRD), salmonellosis, infectious coryza, pasteurellosis
- Swine: Bacterial enteritis, respiratory disease complex, MMA syndrome, Glasser's disease
- Cattle: Bovine respiratory disease (BRD), calf enteritis
- Companion Animals: Pyoderma, UTI, prostatitis, otitis, pneumonia, deep-seated infections
Sourcing Enrofloxacin: Key Checks
Documentation
Request CoA with full HPLC purity and related substances data. Ciprofloxacin content is the key impurity indicator — it should be ≤ 0.2%. Monitor for fluoroquinolone-class degradation products (decarboxylated and ring-opened derivatives).
Red Flags
Ciprofloxacin impurity above 0.5% indicates degradation during synthesis or storage, decarboxylated derivative above 0.2% suggests exposure to heat or light, water content above 1.0%, and reluctance to provide full impurity profile data.
Packaging & Logistics
Standard: 25 KG/DRUM. Enrofloxacin is photosensitive — store in light-protected containers at controlled room temperature (15-30°C). Verify container integrity upon receipt; moisture ingress accelerates degradation.
Market Context
Global enrofloxacin market is one of the largest veterinary antibiotic segments, driven by poultry and swine demand in Asia, Latin America, and Africa. Regulatory restrictions in the US and EU are creating a two-tier market. China dominates API production. Market report