Flunixin
Why has my veterinarian prescribed this medicine?
Flunixin is a non-steroidal anti-inflammatory drug used to relieve pain and inflammation. Your veterinary surgeon may prescribe flunixin to reduce pain in arthritis or following surgical operations. Your veterinarian may administer flunixin by injection to treat shock.
How does this medicine work?
Flunixin blocks the cyclo-oxygenase enzyme, which is involved in the production of prostaglandins. Prostaglandins are substances that trigger pain and inflammation, therefore these responses are reduced.
How do I give this medication?
- Give this medication to your pet as directed by your veterinarian. READ THE LABEL CAREFULLY.
- Try to give this medication at about the same time each day.
- For chronic arthritis, this medicine may be given for a few days of every week. Have a reminder system in place to indicate when the next dose should be given.
- DO NOT give the pet more medicine than directed and DO NOT give more often than directed.
- Do not give this medication for longer than directed.
- Try not to miss giving any doses.
What do I do if I miss giving a dose?
Give the dose as soon as possible. If it is almost time for the next dose, skip the missed dose, and continue with the regular schedule. Do not give the pet two doses at once.
How do I store this medicine?
Keep this medicine out of reach of children. Store this medicine in a cool, dry place at room temperature. Store away from heat and direct sunlight. Do not store this medicine in the bathroom, near the kitchen sink or in damp places. The medicine may break down if exposed to heat or moisture.
Potential side effects
- Although a drug has potential side effects, it does not mean that there is necessarily a high risk of any of these occurring. Tell your veterinarian if your pet is less than 6 weeks of age. Tell your veterinarian if you think your pet may be pregnant.
- Your veterinarian may need to monitor your pet's blood to check for abnormalities.
- Potential side effects of flunixin include mild stomach upset and vomiting. Notify your veterinarian if side effects appear and remain troublesome.
- Other side effects may occur, if you notice anything unusual, contact your veterinarian.
Possible drug interactions
- Make sure to tell your veterinarian what other medication you are giving to your pet because flunixin must not be administered with other non-steroidal anti-inflammatory drugs.
- Quite often your veterinarian may prescribe two different medications, even if a drug interaction may occur. In this case, your veterinarian may vary the dose and/or monitor your pet more closely.
- Drugs may interact such that they can cause an increased or decreased effect or side effects. Current use of nephrotoxic drugs should be avoided. Concurrent use of other highly plasma-protein bound drugs may compete with flunixin and result in toxic effects.
- Contact your veterinarian if your pet experiences any unusual reactions when different medications are given together.
© Copyright 2025 LifeLearn Inc. Used and/or modified with permission under license. This content written by LifeLearn Animal Health (LifeLearn Inc.) is licensed to this practice for the personal use of our clients. Any copying, printing or further distribution is prohibited without the express written consent of LifeLearn. This content does not contain all available information for any referenced medications and has not been reviewed by the FDA Center for Veterinary Medicine, or Health Canada Veterinary Drugs Directorate. This content may help answer commonly asked questions, but is not a substitute for medical advice, or a proper consultation and/or clinical examination of your pet by a veterinarian. Please contact your veterinarian if you have any questions or concerns about your pet’s health. Created on Jul 28, 2015.