New generic drug for bovine respiratory disease is on the market

A generic therapy recently approved by the FDA for the treatment of bovine respiratory disease (BRD) and control of BRD-associated fever in beef and nonlactating dairy cattle is now available on the US market. This florfenicol and flunixin meglumine injectable solution (nixiFLOR; Parnell Technologies) is the first generic bioequivalent to Resflor Gold (Merck Animal Health), a nonsteroidal anti-inflammatory drug (NSAID) with the same active ingredients.^1,2

“At Parnell, we are committed to bringing high-quality, proven products to market with the reliability and pricing veterinarians and producers need,” Pablo Lamberto, president of US operations for Parnell Technologies, said in a news release.¹ “nixiFLOR delivers exactly that, competitive pricing and bioequivalent performance that cattle operations can depend on.”

BRD is a leading cause of illness and death in cattle production systems, with nearly 20% of cattle raised for beef production requiring treatment for the disease during their lifetimes, according to Matthew Scott, DVM, PhD, assistant professor of microbial ecology and infectious disease for the College of Veterinary Medicine and Biomedical Sciences at Texas A&M University. Multiple factors play a role in BRD development, including genetic susceptibility, suppression of the immune system, stress, comingling with sick cattle, sudden climate shifts, and exposure to pathogens (bacterial, viral, and/or parasitic).³

“One of the earliest signs of disease, particularly BRD, is that cattle will tend to lag behind or isolate themselves from the rest of the group,” Scott said in a Texas A&M Pet Talk news release.³ “Other clinical signs can include fever greater than 104 °F, discharge from the nose and eyes, coughing, a tilted head/ear position, and signs of depression, such as decreased appetite, slow body movement, and an unwillingness to stand.”

According to Parnell Technologies, nixiFLOR targets BRD pathogens by combining antimicrobial treatment with anti-inflammatory effects in a single subcutaneous injection. The therapy is designed to help cattle recover quickly and remain on feed by reducing fever. Available by prescription only, the therapy also helps decrease labor for veterinary professionals and chute time for their patients through a single-dose administration.¹

nixiFLOR’s approved label specifies a single subcutaneous injection in the neck at a dose providing 40 mg florfenicol/kg and 2.2 mg flunixin/kg (equivalent to 6 mL per 100 lb). Additionally, the label limits injection volume to no more than 10 mL per site and establishes a 38-day withdrawal interval for animals entering the food supply.^4-6

“BRD remains one of the most significant challenges in cattle production,” Justin Miller, vice president of US commercial operations for Parnell Technologies, said in the release.¹ “nixiFLOR provides a trusted dual-action solution that helps protect herd health while supporting producer profitability.”

Both nixiFLOR and Resflor GOLD are indicated for BRD associated with key bacterial pathogens, including Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, and Mycoplasma bovis. Clinicians should note that the NSAID component may transiently reduce fever and clinical signs. Cattle that have been administered the drug should be reevaluated per label instructions, and antimicrobial stewardship principles should guide product selection and use.^4,5

References

1. Parnell launches nixiFLOR—first FDA-approved generic florfenicol + flunixin combination for BRD. News release. Parnell Technologies. April 1, 2026. Accessed April 2, 2026. https://www.businesswire.com/news/home/20260401078122/en/Parnell-Launches-nixiFLOR---First-FDA-Approved-Generic-Florfenicol-Flunixin-Combination-for-BRD
2. Resflor Gold (florfenicol and flunixin meglumine). Merck Animal Health. Accessed April 2, 2026. https://www.merck-animal-health-usa.com/products/resflor-gold/
3. Texas A&M University College of Veterinary Medicine & Biomedical Sciences. The cattle battle: bovine respiratory disease. Pet Talk. June 30, 2022. Accessed April 2, 2026. https://vetmed.tamu.edu/news/pet-talk/bovine-respiratory-disease/
4. Alaburda R. FDA approves first generic florfenicol-flunixin injectable (nixiFLOR) for bovine respiratory disease. dvm360. January 23, 2026. Accessed April 2, 2026. https://www.dvm360.com/view/fda-approves-first-generic-florfenicol-flunixin-injectable-nixiflor-for-bovine-respiratory-disease
5. Resflor Gold prescribing information. Merck Animal Health; 2024. Accessed April 2, 2026. https://merckusa.cvpservice.com/product/basic/view/1047298
6. FDA approves first generic florfenicol and flunixin meglumine injection for bovine respiratory disease and associated pyrexia in beef and non-lactating dairy cattle. News release. FDA. January 22, 2026. Accessed April 2, 2026. https://www.fda.gov/animal-veterinary/cvm-updates/fda-approves-first-generic-florfenicol-and-flunixin-meglumine-injection-bovine-respiratory-disease