By Lauren Forsythe, PharmD, DICVP; Rania Gollakner, BS, DVM, MPH

What is firocoxib?

Firocoxib (brand names: Previcox®, Equioxx®) is a nonsteroidal anti-inflammatory medication (NSAID) used to treat pain and inflammation in dogs and horses. It is most frequently used to treat arthritis and pain after surgery or trauma.

It may also be effective in treating transitional cell carcinoma (a type of cancer) in dogs; however, this use is not FDA-approved and is considered “off label” or “extra label”. Many drugs are commonly prescribed for off-label use in veterinary medicine. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label.

How is firocoxib given?

  • Firocoxib is given by mouth in the form of a chewable tablet, and may also be compounded into a liquid form.
  • It may be given with or without food; however, if vomiting occurs when dosed on an empty stomach, give future doses with food or a treat.
  • Measure liquid forms of the medication carefully.

This medication will take effect quickly, in about 1 to 2 hours, and improvement in clinical signs should follow.

What if I miss giving my pet the medication?

If you miss a dose, give it when you remember. However, if it is close to the time for the next dose, skip the dose you missed, give it at the next scheduled time, and return to the regular dosing schedule. Never give your pet two doses at once or give extra doses.

Are there any potential side effects?

Like other NSAIDs, firocoxib can affect the gastrointestinal tract with the following side effects:

  • vomiting
  • lack of appetite
  • decreased appetite

SERIOUS ADVERSE REACTIONS associated with this drug may occur without warning and could, in rare cases, lead to death. If any of the following signs develop, stop giving firocoxib and contact your veterinarian immediately:

  • persistent decreased appetite or vomiting
  • changes in bowel movements
  • changes in behavior
  • changes in energy levels
  • incoordination
  • seizures
  • aggression
  • yellow skin/gums
  • skin changes
  • changes in drinking or urination habits

Never give firocoxib prescribed for one dog in your household to another pet without first consulting your veterinarian. Firocoxib is not approved or recommended for use in cats.

This moderate-acting medication should stop working in a few days, although effects can be longer in pets with liver or kidney disease. Most drug-related adverse effects resolve completely when the drug is withdrawn and appropriate veterinary care is initiated.

Are there any risk factors for this medication?

Firocoxib SHOULD NOT BE USED in pets that:

  • are allergic to firocoxib or other NSAIDs
  • are younger than seven months old
  • are currently taking a corticosteroid or another NSAID

DO NOT USE THE TABLETS IN DOGS LESS THAN 12.5 LB (5.7 KG) as the medication cannot be accurately dosed in patients that small.


  • have gastrointestinal ulcerations
  • have bleeding disorders

Firocoxib SHOULD BE USED CAUTIOUSLY in patients:

  • with kidney, liver, or heart disease
  • that are dehydrated
  • that have low blood pressure
  • that are on diuretic medications
  • that are elderly, pregnant, or lactating

Are there any drug interactions I should be aware of?


Certain medications may interact with firocoxib, so it is important to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your dog is taking before starting any new treatment, including:

  • ACE inhibitors like benazepril (Fortekor®) and enalapril (Enacard®)
  • Furosemide
  • Fluconazole

Is any monitoring needed with this medication?

  • Your veterinarian should perform a physical examination and baseline bloodwork including a CBC, liver enzymes, kidney function, electrolytes and urinalysis before your pet starts firocoxib and periodically during treatment with this medication. It is important to attend these follow-up appointments.
  • Your veterinarian may recommend recheck examinations to ensure the medication is working adequately to manage pain.
  • At home, monitor for any side effects such as those noted above. If any side effects occur, discontinue the medication and contact your veterinarian.

How do I store firocoxib?

  • Ensure firocoxib is stored in a tightly closed container and secured inside a cabinet to prevent accidental ingestion.
  • Store at room temperature between 59°F and 86°F (15°C and 30°C). Refer to the label on compounded forms of this medication for storage recommendations.
  • Keep the container out of reach of children and pets.
  • Store compounded forms of this medication according to the label.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. If your dog receives too much of this medication, it can have serious effects on the gastrointestinal system, liver, or kidneys.

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