First Combination Product Approved For Several Years

Many of us recall that many years ago there were several combination drugs for cattle. For example, Pen-Strep or Azimycin, which were a combination of two antibiotics, a steroid and an antihistamine, all in one bottle. These products were pulled in the interests of meat safety and beef quality assurance.

Today, with more thought on animal welfare, we will often prescribe an anti-inflammatory/ painkiller together with an antimicrobial. Veterinarians try to replace the more traditional usage of steroids with the NSAIDs (non-steroidal anti-inflammatory drug). Although there are generics out now as well as other families of NSAIDs, Flunixin or Banamine was the first on the market.

Resflor is a combination of Banamine and florfenicol, another previously approved antibiotic marketed under the trade name of Nuflor. As with all Pr. (prescription) drugs it requires a prescription and a valid VCPR (veterinary client patient relationship) in order to purchase and use.

On first glance, the benefit of any combination product is using fewer needles. In keeping with beef quality assurance, the manufacturer (Intervet Schering Plough Animal Health) has licensed Resflor for subcutaneous use only at the same dosage as Nuflor (six cc per 45 kg or 100 lbs.) and the blood levels persist for four days.

There are several interesting things to note about this product. While the spectrum of organisms it is effective against is the same as Nuflor, the blood levels are reached more quickly and stay higher for the first 24 hours. This is most likely the result of the anti-inflammatory effects of the flunixine, allowing the drug to more quickly penetrate the site of infection. This product is primarily approved for the respiratory pathogens. Cattle will look clinically better as the flunixin decreases the pyrexia (fever), improves the clinical depression and improves the animal’s ability to breath.

This then allows time for the antibiotic to start working and as a result decreases the amount of lung which becomes consolidated (solidified). Once a portion of the lung becomes consolidated, it loses its ability to take in air. The cattle with more consolidation grow more slowly and this consolidated tissue may abscess, resulting in reoccurrence of pneumonia down the road. The quicker pneumonias are treated, the less resulting consolidation or scarring and adhesions of the lungs.


Because this is the first combination product on the market for several years, Health Canada’s Veter inary Drug Directorate has made the slaughter withdrawal 60 days, slightly longer than the individual drug Nuflor. It is also not to be given to any dairy cattle milking or dry, and to veal calves.

As mentioned earlier, this is also a prescription product so will be used under a direct veterinary client patient relationship. It will primarily be used for respiratory disease on calves or light feeder cattle where the 60-day slaughter withdrawal is easily followed. Heavy feeder cattle will in most cases find other products being used with shorter to no withdrawals.

In doing some of the approval work it was also found that penetration of the antibiotic into areas such as skin, muscle, soft tissue in the foot as well as the brain and areas around the eye will make it useful in treating a large number of maladies. This will be up to your veterinarian and yourself as to what these conditions are. With time more of them will appear on the label.

It should be noted as well that unlike Banamine by itself, which is given intravenously, used in this combination it is given subcutaneously with little swelling at the injection site. With six cc /100 lbs. (45 kgs) that is quite a large injection volume and in larger calves I would still split that over at least two injection sites. The actual recommendation is no more than 10 cc per site. It is still relatively thick like Nuflor so must be kept warmer in winter. Use a larger-bore needle (16 gauge) to facilitate overcoming the poorer syringability.

The Banamine dosage in Resflor is formulated to be the same as the 24-hour dosage of two cc per 45 kgs if given individually. What this means is the Banamine in it will last better than 24 hours which is often all you need.

It is cheaper than the combination of the two products, and in my mind over time Resflor sales will pretty much take over from Nuflor. It has all the benefits you and your veterinarian have derived from Nuflor with the additive benefits of an NSAID added in. It’s a welcome addition to today’s arsenal developed primarily for bovine respiratory disease.


Itwillprimarilybeusedforrespiratorydisease oncalvesorlightfeedercattlewherethe60-day slaughterwithdrawaliseasilyfollowed.

About the author


Roy Lewis practised large-animal veterinary medicine for more than 30 years and now works part time as a technical services veterinarian for Merck Animal Health.



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