Prevail and Banamine contain the exact same active ingredient, flunixin meglumine, at the same concentration: 50 mg per milliliter. Banamine is the original brand name, and Prevail (made by VETone) is a generic equivalent. They work the same way, treat the same conditions, and are dosed identically.
Same Drug, Different Label
Banamine was the first FDA-approved flunixin meglumine product for horses and cattle, making it the “reference listed” drug that all generics are measured against. Prevail is one of several generic versions that followed. Both are injectable solutions available in multi-dose vials (100 mL and 250 mL sizes), and both deliver 50 mg of flunixin per milliliter. The inactive ingredients and carrier solution can differ slightly between brands, but the drug your animal absorbs is chemically identical.
The main practical difference is price. Generics like Prevail typically cost less than the Banamine brand name. Your veterinarian may stock whichever version they prefer or can source more easily, and the clinical outcome will be the same.
What Flunixin Meglumine Treats
Flunixin meglumine is a nonsteroidal anti-inflammatory drug (NSAID), similar in concept to ibuprofen in human medicine but formulated specifically for large animals. In horses, it’s approved for two primary uses: relieving pain and inflammation from musculoskeletal problems (joint soreness, soft tissue injuries) and alleviating the visceral pain of colic. It’s one of the most commonly used medications in equine practice for exactly these reasons.
In cattle, the approved uses are different. Flunixin meglumine controls fever associated with bovine respiratory disease, endotoxemia (a systemic reaction to bacterial toxins), and acute mastitis. It also reduces the dangerous inflammation that comes with endotoxemia.
Dosing and Administration
Whether you’re using Prevail or Banamine, the dosing is identical because the drug and concentration are the same.
For horses, the standard dose is 0.5 mg per pound of body weight, which works out to 1 mL per 100 pounds. For musculoskeletal conditions, this can be given intravenously or intramuscularly once daily for up to five days. For colic pain, the same dose applies, but intravenous administration is recommended for faster relief.
For cattle, the dose ranges from 0.5 to 1 mg per pound (1 to 2 mL per 100 pounds), given by slow intravenous injection. This can be administered once daily or split into two doses 12 hours apart, for up to three days. For acute mastitis, the higher end of that range is used as a single intravenous dose. Flunixin meglumine is approved only for intravenous use in cattle, not intramuscular.
Why the Route of Injection Matters
One important safety detail applies to both Prevail and Banamine equally. In horses, intramuscular injection carries real risks. In rare cases, it has been linked to fatal or nonfatal clostridial infections, which are caused by bacteria that thrive in damaged muscle tissue. Localized reactions at the injection site, particularly in the neck, can also occur, including swelling, stiffness, and hardened tissue. For these reasons, many veterinarians prefer to give flunixin intravenously whenever possible.
In cattle, intramuscular injection is not just risky but actually not approved. Giving the drug into muscle rather than a vein has caused violative drug residues in meat from cattle sent to slaughter, which is both a food safety concern and a regulatory violation.
Side Effects to Know About
Like all NSAIDs, flunixin meglumine can cause gastrointestinal problems, especially when used at higher-than-recommended doses or for extended periods. Research on foals found that those given six times the normal dose developed significantly more gastrointestinal ulceration, particularly in the cecum, compared to foals given saline. At the recommended dose, however, there were no significant differences in bloodwork or gut pathology compared to untreated foals.
Kidney damage is another recognized risk with NSAID overuse in horses. Renal papillary necrosis, a condition where tissue in the kidneys dies from reduced blood flow, has been documented in horses receiving NSAIDs. Staying within the recommended dose and duration (no more than five consecutive days in horses) is the main way to minimize these risks. Dehydrated animals are especially vulnerable, which is worth noting since horses with colic often aren’t drinking normally.
Withdrawal Times for Food Animals
If you’re using flunixin meglumine in cattle, withdrawal periods are critical. Cattle must not be slaughtered for food within four days of the last treatment. The drug is not approved for use in lactating or dry dairy cows, and no withdrawal period has been established for preruminating calves, so it should not be used in calves intended for veal. Horses treated with flunixin meglumine are not eligible for food use at all.
Available Formulations
Prevail is currently available as an injectable solution only. Banamine, being the older and more established brand, has historically been associated with a wider range of formulations, including an oral paste and granules for horses. If you need a non-injectable option, ask your veterinarian which flunixin meglumine products are available in the formulation you need. The injectable form should never be given orally without specific veterinary guidance, as the concentration and formulation are designed for injection.