Pharmacotherapeutic group: Anthelmintics, benzimidazole derivatives -fenbendazole
ATCvet Code: QP52AC13
Pharmacodynamic properties
Fenbendazole is an anthelmintic belonging to the benzimidazole-carbamate group. It acts by interfering with the energy metabolism of the nematode.
Fenbendazole inhibits the polymerisation of tubulin to microtubules. This interferes with essential structural and functional properties of the cells of helminths, such as formation of the cytoskeleton, formation of the mitotic spindle and the uptake and intracellular transport of nutrients and metabolic products. Fenbendazole has activity against Ascaridia galli (adult stage) and Heterakis gallinarum (L5 and adult stages) in chickens and against
H. gallinarum (adult stage) in pheasants.
Pharmacokinetic particulars
After oral administration, fenbendazole is only partially absorbed. Following absorption, fenbendazole is rapidly metabolised in the liver mainly to its sulphoxide (oxfendazole) and further to its sulphone (oxfendazole sulphone) In chickens oxfendazole sulfone is the main component detected in plasma, accounting for about 3/4 of the total AUC (ie the sum of the AUC for fenbendazole, oxfendazole and oxfendazole sulphone). Fenbendazole and its metabolites are distributed throughout the body, reaching highest concentrations in the liver.
The elimination of fenbendazole and its metabolites occurs primarily via the faeces.
PHARMACEUTICAL PARTICULARS
List of excipients: Maize Starch and starch (pregelatinised)
Major incompatibilities: In the absence of compatibility studies, this veterinary medicinal product must not be mixed with other veterinary medicinal products.
Special precautions for storage
Veterinary medicinal product as packaged for sale: no special storage precautions.
After first opening of the immediate packaging: do not store above 25°C.
Medicated feed (mash and pelleted): no special storage precautions.
Special precautions for the disposal of unused veterinary medicinal product or waste materials derived from the use of such products:
Any unused veterinary medicinal product or waste materials derived from such veterinary medicinal products should be disposed of in accordance with local requirements. The product should not enter water courses as this may be dangerous for aquatic organisms