Flunixin is a non-steroidal anti-inflammatory drug (NSAID), analgesic, and antipyretic used in horses. It is often formulated as the meglumine salt. In the United States, it is FDA-regulated, and may only be lawfully distributed by order of a licensed veterinarian.
Because it targets the inflamed tissue, flunixin is mainly used for colic
pain, muscle pain, and joint disease, as well as to alleviate fevers and pain, and prevent endotoxemia
. It is also effective in injuries of the eye.
The full analgesic and antipyretic effects usually occur 1-2 hours following treatment, but there is often an effective analgesic effect within approximately 15 minutes.
Side effects and precautions
Flunixin should not be given for more than five days. Like most NSAIDs it can produce gastrointestinal
side effects if the drug is given in high doses or over several days. GI ulceration is the most common side effect, especially in the animal's large colon or stomach, and is most likely to occur if the drug is given for a prolonged period. Other side effects include kidney damage and bleeding problems. It should be used with caution in horses with kidney or liver disease.
Flunixin does not treat the underlying problem causing the fever or pain, only the symptoms. Additionally, pain is often useful for a veterinarian to diagnose a horse's condition, and masking it with flunixin may do more harm than good. For this reason, there are many vets who do not wish for the animal to be given Flunixin if colic is suspected, preferring to withhold the drug until the need for colic surgery has been determined. It is therefore advisable to ask the horse's vet before giving the drug.
Flunixin is a prohibited class A drug under FEI rules, and its use is prohibited or restricted by many other equestrian organizations. It can be detected in the blood for 2-3 days, and in the urine up to 15 days following administration.
Combining with other drugs
Flunixin should not be combined with other NSAIDs or corticosteriods, as this increases the risk of gastric ulcers, right dorsal colitis, and kidney disease. Additionally, veterinarians should use caution when combining it with anticoagulants or aminoglycoside antibiotics. Flunixin is commonly used with omeprazole, sucralfate, and cimetidine to protect the gastrointestinal tract.
Flunixin may be given orally as a paste or as granules in feed. It can also be used intramuscularly or intravenously, although because it is very irritating to tissue, the IV route is preferred, and in cattle it is the labeled route of administration.
Dosages are usually reduced for ponies, who are more at-risk for NSAID side-effects, as well as horses with decreased liver or kidney function (such as older horses).
In the USA the trade names are Banamine
, and Meflosyl Solution
. In the UK, South Africa and Australia a common trade name is Finadyne
- Forney, Barbara C, MS, VMD.Equine Medications, Revised Edition. Blood Horse Publications. Lexington, KY. Copyright 2007.