Branded vs. Generic Dewormers: Pick Your Products Wisely

beef producer closing cows into pen

You're spending hard-earned money on dewormers. But are they working hard for you?

“Dewormers are just like everything else – you get what you pay for,” said Sarah Spidel, DVM, Lewisburg Animal Hospital. “If you don’t want your feet and legs to hurt after a long day of work, you’re not going to go out and buy the cheapest shoes you can find…the same concept can be applied to dewormers.”

With the passage of time, patent rights have expired on the active ingredients contained in brand name dewormers and predictably, several generic products are now on the market. For the original clearance of each product, numerous studies were conducted regarding safety, residues, formulation and efficacy. However, little information on the efficacy of new generic products has been published.1

While the active ingredient may be the same, there can be many differences in how a dewormer is manufactured, the quality measures taken, and even the other ingredients included. As a result, there can be quite a difference in how some generic products perform.


What to look for on the product label

Product labels contain important information that can help you gauge the value of each dewormer on the shelf. When looking at product labels, Jody Wade, DVM, Boehringer Ingelheim, encourages producers to answer the following questions:

  • How many parasites is the dewormer able to control? “On some of the labels out there, it’s hard to find what parasites the products have been tested against, and what each product has actually been proven to kill. Be sure the product is backed by extensive research.”
  • Is it weatherproof? You don’t want the product to wash off if it happens to rain later in the day, or if the cattle decide to go for a swim in a nearby water source.
  • Does the product come with a satisfaction guarantee? Companies that offer product satisfaction guarantees trust in their products, which gives customers confidence that they can too.

“If the product is not able to do the job you paid for it to do, it’s worthless in my opinion,” said Dr. Spidel. “The inexpensive dewormers are not saving you money if they end up costing you reduced herd performance.”


Avoid parasite resistance on your operation

“It’s not easy to reverse parasite resistance in a herd, and research has shown that generic deworming products were not as efficacious as branded products on the market,” said Dr. Wade.1 “Choosing a dewormer with proven efficacy and following sustainable deworming best practices is one of the best ways to make sure resistance doesn’t occur on your operation.”  

Dr. Spidel adds that it’s also difficult for the dewormer to do its job if not administered correctly. Read the label to be certain the product is stored correctly, the dose you’re administering is accurate for the weight of animal you’re treating, and that your equipment is properly functioning prior to treating the animals. Pour-on dewormers should be applied along the topline in a narrow strip from withers to tailhead.

Finally, Drs. Wade and Spidel encourage producers to consult a local veterinarian. He or she can help you choose the best product(s) for your herd and identify ways to boost the efficacy of your deworming program. Your grazing period, the age and category of your animals, your operation type and history of the pasture are all considerations to discuss.



1 Yazwinski TA, Tucker CA, Hornsby J, et al. A field trial evaluating the efficacy of several commercial ivermectin pour-on products in cattle. University of Arkansas, Arkansas Cattle Business, 20(9), 44-46. 2004.


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