Diclazuril belongs to the triazine benzonitrile compound class and is a highly effective, low-toxicity, broad-spectrum anticoccidial drug, appearing as a nearly white or light yellow powder. Melting point: 289～292℃. It is practically insoluble in water and ethanol, but soluble in alkaline water, slightly soluble in dimethylformamide, and sparingly soluble in tetrahydrofuran.
Pharmacokinetic Parameters:
Concentration-dependent drug (drug effect is related to concentration within a certain range). After a single oral gavage of 10mg/kg BW diclazuril premix in chicks, the pharmacokinetic process in the body conforms to a one-compartment model with first-order absorption. The time to peak concentration (Tmax) is 1.64h, the elimination half-life (T1/2β) is 24.29h, the area under the drug concentration-time curve (AUC) is 349.47 (mg/L).h, and the plasma clearance rate (CL) is 0.03mg/kg.h. The results indicate that diclazuril is absorbed relatively quickly in chicks and eliminated slowly from the plasma, classifying it as a slow-elimination drug.
Pharmacological Action:
Diclazuril acts on both asexual and sexual reproductive stages of Eimeria tenella within the host. It inhibits the formation and release of first and second-generation schizonts and merozoites, and simultaneously inhibits fertilization, ultimately achieving the effect of killing coccidia.
Indications:
It mainly targets the second-generation schizonts in the sexual cycle of Eimeria tenella. However, it is ineffective against the schizonts of Eimeria maxima and Eimeria brunetti. It acts on the zygote stage of Eimeria maxima and is highly effective against the microgametocyte stage of Eimeria brunetti. Diclazuril also has an inhibitory effect on the sporulation of oocysts.
Clinical Use:
Taking a 0.5% diclazuril solution as an example, diclazuril raw material is insoluble in water, and the premix is absorbed relatively slowly. The solution is convenient to use and absorbed more quickly. It is mainly used for the prevention and treatment of coccidiosis in the early growth stage of broilers.
Dosage:
0.5% Diclazuril Solution (Pharmacopoeia dosage: 0.1～0.2ml per 1L of water for chickens). Due to the widespread development of coccidial resistance, a clinical recommendation is 3000-5000kg of water per 1L of solution. Concentrated administration (concentration-dependent drug) is recommended, to be consumed within 4 hours, for 5 consecutive days. Note that diclazuril has a short effective period, and its anticoccidial effect weakens immediately after stopping the medication for one day. Therefore, continuous use for 5 days without interruption is necessary to avoid the development of cross-resistance. Frequent (more than 6 months) rotation of medication is required.
Common Preparations:
1% Diclazuril Granules; 0.5% Diclazuril Solution; 0.2%, 0.5%, 5% Diclazuril Premix; 0.2%, 0.5% Diclazuril Premix (for aquaculture).
Drug Interactions:
Diclazuril solution is prepared with organic solvents and is generally alkaline. Avoid using it together with acidic drugs (such as Vitamin C, Doxycycline, etc.) as much as possible. The solution has a certain organic matter solubility, so avoid contact with human skin.
Withdrawal Period:
Chickens: 5 days; Laying hens: prohibited during the laying period.