Quick Facts
| CAS Number | 69004-03-1 |
|---|---|
| Molecular Formula | C18H14F3N3O4S |
| Molecular Weight | 425.382 |
| Pharmacopoeia | CVP/USP |
| Packaging | 25 KG/DRUM |
Product Overview
Toltrazuril was developed by Bayer AG in the 1980s as part of a systematic search for compounds that could treat — not merely prevent — coccidiosis. This distinction is fundamental to understanding toltrazuril's place in veterinary medicine. Ionophore anticoccidials (monensin, salinomycin, narasin), which had dominated poultry production since the 1970s, are preventive agents: they must be fed continuously in the diet to suppress coccidial replication. They work by killing sporozoites before they invade intestinal cells. But once a clinical coccidiosis outbreak has begun — once the flock is shedding blood in the droppings — ionophores are ineffective, because the parasites are already inside the intestinal cells, beyond reach. Toltrazuril was the first compound that could kill coccidia at any intracellular stage.
Toltrazuril belongs to the symmetrical triazinetrione class, structurally unrelated to any previous anticoccidial. Its mechanism involves interference with nuclear division and mitochondrial function in the parasite, causing swelling and destruction of the endoplasmic reticulum. Unlike ionophores that target only extracellular sporozoites, toltrazuril acts against schizonts (the asexual multiplication stage), gamonts (the sexual stage), and merozoites — essentially the entire intracellular life cycle of Eimeria. This broad stage coverage is what makes the 2-day treatment protocol possible. A critical feature is that toltrazuril does not completely prevent the early stages of infection: some parasites complete schizogony before the drug exerts its effect. This partial exposure allows the host to develop natural immunity — a crucial advantage for pullets and breeders where long-term immunity is essential.
Toltrazuril is a prodrug. After oral administration, it undergoes hepatic oxidation to toltrazuril sulfone (ponazuril), which is the primary active metabolite responsible for in vivo anticoccidial activity. Ponazuril is subsequently marketed as a separate drug, primarily for equine protozoal myeloencephalitis (EPM) in horses and coccidiosis in dogs and cats. The prodrug relationship means that when sourcing toltrazuril API, both the parent compound purity and the metabolic activation pathway matter: the pharmacokinetics of conversion to ponazuril can be affected by particle size, polymorphic form, and formulation characteristics of the oral suspension or drinking water solution.
As of mid-2026, toltrazuril is one of the most important anticoccidial APIs in global poultry production. Coccidiosis is estimated to cost the global poultry industry over USD 14 billion annually in mortality, reduced weight gain, poor feed conversion, and control costs. Toltrazuril's role is irreplaceable in the "shuttle" and "rotation" programs used to manage anticoccidial resistance — it is alternated with ionophores and chemical anticoccidials to prevent the emergence of resistant Eimeria strains. The demand for toltrazuril is increasingly driven by the global transition away from antibiotic growth promoters (AGPs) and the expansion of "no antibiotics ever" (NAE) poultry production, where toltrazuril is permitted because it is not an antibiotic. China dominates global toltrazuril production, and KingWish supplies GMP-certified toltrazuril meeting CVP and USP specifications.
Quality Specifications
| Purity (HPLC) | ≥ 98.0% (dried basis), per CVP/USP monograph |
|---|---|
| Related Substances | Any single individual impurity ≤0.5%; total combined impurities ≤1.0% |
| Particle Size (Micronized) | D90 ≤ 20 micrometers (critical for oral suspension dissolution) |
| Residual Solvents | Compliant with ICH Q3C |
| Heavy Metals | ≤ 20 ppm |
| GMP Status | Manufactured under ICH Q7 GMP conditions |
Veterinary Applications
Poultry Coccidiosis (Broilers & Layers)
2.5% oral solution at 25 ppm (7 mg/kg) in drinking water for 2 consecutive days. Timed at 14-15 days for broilers. Single 2-day treatment typically sufficient. Does not interfere with natural immunity development.
Piglet Coccidiosis (Isospora suis)
Single oral dose of 20 mg/kg at 3-5 days of age. Highly effective against Isospora suis, the primary cause of piglet coccidiosis. Reduces oocyst shedding, diarrhea severity, and pre-weaning mortality.
Therapeutic Areas
- Poultry (broilers): Treatment and prevention of coccidiosis caused by Eimeria acervulina, E. maxima, E. tenella, E. necatrix, and E. brunetti
- Poultry (breeders/layers): Immunity-compatible coccidiosis control that allows natural immunity while preventing clinical disease
- Swine (piglets): Isospora suis coccidiosis — single oral dose at 20 mg/kg, 3-5 days of age
- Cattle (calves): Eimeria bovis and E. zuernii coccidiosis — oral suspension
- Sheep (lambs): Eimeria coccidiosis — oral administration of toltrazuril suspension
Sourcing Toltrazuril API: Key Checks
Documentation
Request CoA with HPLC purity data, related substances profile, particle size distribution (critical for oral suspensions — request micronized grade), residual solvent statement (ICH Q3C), heavy metals, and GMP certificate. For EU markets, verify VICH GL18 MRL compliance for food-producing animals.
Red Flags
Coarse particle size (D90 above 50 micrometers causes poor suspension stability and erratic oral absorption), elevated related substances indicating incomplete synthesis or degradation, missing particle size data on CoA, and non-micronized material offered for oral suspension formulations.
Packaging & Logistics
Standard: 25 KG/DRUM with PE liner. Store at room temperature in airtight containers, protected from light. Micronized toltrazuril is more hygroscopic than coarse material — ensure packaging integrity. Standard lead time 6-8 weeks. Air and sea freight options available.
Market Context
Toltrazuril demand is growing as the poultry industry transitions to NAE (No Antibiotics Ever) production, where toltrazuril is a permitted non-antibiotic anticoccidial. The China Veterinary Pharmacopoeia standard (CVP) is recognized in Asian, African, and Latin American markets. Patent expiry has enabled generic API production, with China dominating global supply.