flunixin

Action and Spectrum

Actions and Spectrum: 

Actions: 

Cattle, pigs, and horses can all benefit from the non-steroidal anti-inflammatory medication flunixin. It has analgesic and antipyretic properties. Meglumine salt preparations for this medication are common. The FDA, or Food and Drug Administration, oversees the regulation of flunixin in the US, and a licensed veterinarian is required to dispense the medication. Flunixin is also known by other trade names, such as Banamine. 

Spectrum: 

Horses: To reduce inflammation and pain related to musculoskeletal diseases in horses. It is also advised to administer a flunixin injection to horses in order to relieve the visceral pain linked to colic. 

Cattle: To manage acute bovine mastitis, endotoxemia-related pyrexia, and Bovine Respiratory Disease (BRD). Additionally recommended for the management of endotoxemia-related inflammation is flunixin injection. It has been shown in clinical trials that flunixin when used in conjunction with oxytetracycline antibiotic therapy, can effectively manage the pyrexia linked to bovine respiratory diseases. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Flunixin injections intramuscularly have occasionally resulted in reports of local responses in horses, especially in the neck, including regional edema, induration, sweating, and stiffness.  

Rarely, horses treated intramuscularly with flunixin injection have been documented to experience both nonfatal and fatal clostridial infections together with other infections. 

Furthermore, uncommon instances of anaphylactic-like reactions in horses and cattle have been documented, some of which have been deadly, especially after intravenous administration. 

Black Box Warning

Black Box Warning: 

Treated cattle must not be slaughtered for at least six days after the latest treatment. Milk from treated animals during treatment and within 36 hours afterward must not be used for food. Avoid use in dry dairy cows. 

Since a withdrawal period in pre-ruminating calves has not been established, avoid use in veal calves. Do not use horses intended for slaughter for food. Keep out of reach of children. 

Contraindication / Caution

Contraindication/Caution: 

Contraindications 

Horses: 

Avoid intra-arterial administration, as inadvertent injection may lead to adverse reactions, including hysteria, ataxia, hyperventilation, incoordination, and muscle weakness. These signs are transient and resolve without antidotal medication within a few minutes. Do not use in horses with hypersensitivity to flunixin meglumine. 

Cattle: 

Intra-arterial administration should be avoided to prevent adverse reactions. Do not use in cattle exhibiting hypersensitivity to flunixin meglumine. The drug is contraindicated in subjects with renal and hepatic disease, cardiovascular impairment, gastrointestinal ulceration, and/or platelet disorders. Dehydrated animals should also avoid its use. 

Cautions 

The use of NSAIDs may pose risks of gastrointestinal, hepatic, or renal toxicity. Patients at higher risk for renal toxicity include those who are dehydrated, on concurrent diuretic therapy, or have hepatic, cardiovascular, and/or renal dysfunctions. Caution is advised when administering potentially nephrotoxic drugs concurrently. 

In those with underlying or pre-existing disorders, NSAIDs may impede prostaglandins that maintain proper homeostatic function, potentially leading to clinically severe illness. Due to the risk of gastrointestinal ulceration, avoid concurrent use with other anti-inflammatory drugs, such as other NSAIDs or corticosteroids. Drug compatibility should be closely monitored in patients requiring adjunctive therapy. If fecal blood or hematuria is noticed, stop using the medication. Avoid administering intravenously quickly. 

Horses: 

The reproductive effects of flunixin in horses are undetermined. Studies in rabbits and rats demonstrated no teratogenicity with flunixin. 

Cattle: 

Avoid use in breeding bulls, as the reproductive effects of Flunixin Injection in this category of cattle have not been studied. NSAIDs may impact parturition and the estrous cycle, potentially delaying estrus onset if administered during the prostaglandin phase. The effects on imminent parturition have not been assessed in controlled studies, and caution is advised to prevent delays in parturition.

Pregnancy / Lactation

Pregnancy consideration:  

No data is available regarding the administration of the drug during pregnancy. 

Breastfeeding warnings:  

No data is available regarding the excretion of drug in breast milk. 

Pregnancy category: 

Category A: well-controlled and satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: No data is available for the drug under this category. 

Pharmacology

Pharmacology: 

The main purpose of flunixin is to temporarily relieve mild to inflammation and moderate pain. It has been used to cure horses’ gastrointestinal pain, lessen sepsis symptoms in horses, and lessen the clinical symptoms of coliform mastitis in cattle. 

Pharmacodynamics: 

Flunixin has anti-inflammatory qualities that last far longer than the time it takes for a drug’s measurable plasma concentration to remain in inflammatory tissues. One category for flunixin meglumine is carboxylic acid. It is thought that cyclooxygenase (COX) enzyme inhibition is the main mechanism of action. Reduced production of cyclooxygenase-derived eicosanoids, such as thromboxanes and prostaglandins, which are important in the pathophysiology of inflammation, is the outcome of this inhibition. 

Pharmacokinetics: 

Absorption 

The bioavailability is 79% (goats). 

The time to achieve peak effect is 15-45 minutes. 

Elimination and Excretion 

Horse serum has a plasma half-life of 1.6 hours after a 1.1 mg per kg single dosage. 

In cattle, the terminal half-life has been reported to range from 3.14 to 8.12 hours.

Adminstartion

Administration: 

The administration of flunixin entails following prescribed guidelines, which may vary depending on the species under treatment. Generally, it can be administered either intravenously or intramuscularly, depending on the specific circumstances. In the case of cattle, sheep, goats, and camels, the recommended dosage ranges from 1.1 mg to 2.2 mg of flunixin per kg of body weight, administered through slow intravenous or intramuscular administration.

The total dose should not exceed 2.2 mg/kg of body weight, and if necessary, it can be repeated at 24-hour intervals for a maximum of 5 consecutive days. For instances of bovine mastitis, a single dose of 2.2 mg/kg body weight can be administered once through slow intravenous or intramuscular injection, with the option to repeat if necessary at 24-hour intervals for up to 5 consecutive days. 

Observing withdrawal periods is crucial, with a 24-hour period recommended for milk and a 5-day period for meat in cattle. For pigs, a withdrawal period of 22 days for meat is advised. 

Adherence to these guidelines and consultation with a veterinarian is essential to ensure the proper and safe administration of flunixin for specific conditions in various animal species.

Patient Information Leaflet

Patient information leaflet 

Generic Name: flunixin 

Pronounced: floo-NIK-sin 

Why do we use flunixin? 

Because of its analgesic (pain-relieving), antipyretic, and anti-inflammatory qualities, flunixin is a nonsteroidal anti-inflammatory medication (NSAID) used in veterinary medicine. It is frequently used to treat pain and inflammation brought on by a variety of ailments in animals, such as lameness, musculoskeletal problems, and discomfort following surgery.

Furthermore, flunixin is used to reduce pain and swelling in cases of respiratory illnesses in cattle as well as colic in horses. It functions by preventing the synthesis of prostaglandins, which are chemicals that increase fever, inflammation, and discomfort. Veterinarians usually prescribe flunixin to treat particular health problems in animals and enhance their overall well-being.