Nicarbazin (C19H18N6O6), a complex of two compounds, 4,4'-dinitrocarbanilide (DNC) and 4,6-dimethyl-2-pyrimidinol (HDP) is an effective drug for preventing intestinal and caecal coccidiosis in poultry. It is used for the prevention rather than the treatment of disease.

Nicarbazin (introduced in 1955) was the first agent with “broad‐spectrum” activity against Eimeria spp. of chickens; it is an equimolar complex of dinitrocarbanilide and dimethylpyrimidinol and still used as a single agent or in combination with polyether antibiotics (narasin, or maduramicin), roxarsone, or antibiotics (lincomycin, bacitracin,flavomycin) for prevention and control of coccidiosis caused by Eimeria spp. (all relevant species) in broiler chickens; there may be problems with side effects occurring during summer; it can cause increased sensitivity to heat stress, which may result in growth depression and even mortality in broilers; death may be due to cell degeneration processes in liver and kidneys; at recommended dose, the drug causes occasionally toxic effects in laying hens like reduced hatchability and interruption of egg laying; Nicarbazin interferes with the formation of the vitelline membrane, separating the egg yolk and egg white. The exact mode of action is unknown, although it is thought nicarbazin interferes with cholesterol metabolism in the formation of the membrane. Eggs from treated birds are described as mottled in appearance, reflecting a porous vitelline membrane. The effect on hatchability is a function of time and dose and the effect is reversible.



Stage of the life cycle affected by the drug:

Its action is primarily directed against developing second‐generation Eimeria schizonts (day 5). 




125 ppm


 Study type  Results
 Acute Inhalation Toxicity - rat LC50 > 0.147 mg/L
 Acute Dermal Toxicity - rat

LD50 > 5,000 mg/kg




Drug combinations: It shows synergistic effect with polyether antibiotics (eg. combination with narasin, monensin or maduramicin);

Broilers given nicarbazin in the starter diet showed increased pigmentation.

One of the principal reasons for DNC residues is the fact that nicarbazin is highly electrostatic, and as a result of residual binding in feed mill production lines, leads to contamination of supposedly nicarbazin-free withdrawal feeds.
Nicarbazin 0.5% represents birth control for birds. This method of pigeon control reduces the overall bird burden at treatment sites.