Norbrook introduces first FDA-approved generic dewormer targeting resistance in livestock

Norbrook launches Defendazole, the first FDA-approved generic fenbendazole oral suspension for cattle and goats, emphasising sustainable parasite control amid rising resistance concerns.

Norbrook has launched Defendazole, a fenbendazole oral suspension that the US Food and Drug Administration has approved as the first generic white drench dewormer for beef and dairy cattle and goats, according to company and FDA statements. The product is intended to treat and control lungworms, stomach worms and intestinal worms, which can undermine feed intake, growth and reproductive performance in cattle. Norbrook says it is bioequivalent to Safe-Guard and is being positioned as a broader access option for both large and smaller operations.

The company says Defendazole is sold in 1-litre and 5-litre bottles and is dosed at 2.3 mg/lb body weight in cattle. For cattle, the label calls for an eight-day meat withdrawal and a 48-hour milk discard period. Norbrook also says the product is dung-beetle friendly, preserving a natural soil benefit that veterinarians and producers increasingly weigh when choosing parasite control products.

Megan Bollin, Norbrook’s technical services veterinarian, has urged producers to work with their veterinarian and use fecal egg count testing to identify parasite burdens and evaluate whether a programme is still working. That advice fits with the FDA’s wider warning that antiparasitic resistance is a growing concern in livestock and that sustainable dewormer use is becoming more important.

Image Source: Norbrook Animal Health