amprolium

Amprolium is a small molecule coccidiostat primarily used in veterinary medicine, especially for the prevention and treatment of coccidiosis in poultry such as chickens, turkeys, and pheasants[1][7]. It is a quaternized derivative of pyrimidine and acts as a thiamine (vitamin B1) antagonist due to its structural similarity to thiamine[3][5][8]. By competitively inhibiting thiamine uptake via blockade of the thiamine transporter in *Eimeria* species (the causative agents of coccidiosis), it disrupts carbohydrate synthesis essential for parasite survival[3][5][8]. Amprolium is effective against several *Eimeria* species including *E. tenella*, *E. necatrix*, and *E. acervulina*. It has a wide margin of safety in poultry but can induce thiamine deficiency at high doses or with prolonged use[3][6]. The drug is rapidly eliminated via the kidneys and does not require an egg withdrawal period when used according to labeling[7].

Brand names

AmprolAmprol 25Amprol25Amprol-25

Other names

1-((4-amino-2-propyl-5-pyrimidinyl)methyl)-2-picolinium chlorideamprolioamprolium hydrochloride