Firocoxib Poisoning in Dogs

Previcox is a brand name version of a non-steroidal anti-inflammatory drug (NSAID), Firocoxib, and is used to relieve post-operative pain or pain in canines who are afflicted with osteoarthritis. Although it is generally a safe medication when given as prescribed there is the possibility of serious toxicity if the dog overdoses on a large amount at once, if your dog has a sensitivity to it, or if it reacts to another chemical in the patient’s blood. You should contact your veterinarian as soon as possible if symptoms develop.

Previcox is a brand name version of a non-steroidal anti-inflammatory drug (NSAID), Firocoxib, designed to relieve pain in canines. NSAIDs have a high level of interactivity with other medications, including herbal remedies.

Either a sensitivity to the Firocoxib that the Previcox is composed of, or an overdose of the substance can        cause damage to the kidneys, liver, or heart. 

• Abdominal pain
• Black tarry stool
• Bruising
• Dehydration
• Diarrhea
• Excessive urination 
• Fatigue
• Itching
• Lethargy
• Loss of appetite
• Rash
• Seizures
• Vomiting, possibly bloody
• Weight gain

Types

Firocoxib/Previcox is just one of several NSAID medications available, and each of them has a slight chance to become toxic if your canine has a sensitivity, if the amount ingested is too high, or if there are any interactions with other drugs. Below are listed other NSAIDs approved by the FDA for use in dogs, and the brand names they are known under.

• Carprofen (Rimadyl, Novocox, Vetprofen, Carprieve, Quellin, Carprofen)
• Deracoxib (Deramaxx)
• Etodolac (EtoGesic)
• Meloxicam (Metacam, Loxicom, Orocam, Meloxicam)

These are common over the counter NSAIDs that humans use, and a few of the more common brands that employ them.

• Aspirin (Bayer, Bufferin, Excedrin)
• Ibuprofen (Advil, Motrin)
• Naproxen Sodium (Aleve)

NSAIDs like Previcox repress the enzyme cyclooxygenase (COX). This enzyme stimulates the production of many substances within the body, including the prostaglandins that contribute to inflammation and pain after cell damage has occurred. The repression of the enzyme reduces the amount of pain by reducing the inflammation, but it also reduces the other prostaglandin functions, such as maintaining blood flow to the kidneys, protecting the stomach lining from acid, and supporting platelet formation. When administered to your pet as directed by your veterinarian these medications are relatively safe, however certain circumstances such as oversensitivity to the drug, overdose, or reactions to other drugs, it can become fatal. If your pet develops symptoms of toxicity due to Previcox or similar NSAIDs, cease administering the drug and contact your animal’s veterinarian right away. 

Certain patients should not take Previcox or should be very closely monitored by the veterinarian. Disorders and conditions that can increase the likelihood of the medication to become detrimental instead of helpful:

• Cardiac disease
• Dehydration
• Gastric ulcers 
• Hepatic disorders
• Hyperproteinemia
• Pregnant or nursing dogs
• Renal disease

Concurrent use of other NSAIDs or any form of steroids should be avoided as that can increase toxicity.

Your veterinarian will need to get your pet’s full history from you, taking special note of the diet and any opportunistic eating as well any concurrent prescriptions or supplements that your dog is on. A complete blood count, biochemistry profile, and urinalysis are likely to be done at this time as well. This will help determine not only the concentration of the drug in the system, but also the functionality of the kidneys and liver. If the condition is due to a reaction from a prescribed administration of Previcox, such as is used to relieve osteoarthritis or post-operative pain, your veterinarian will have taken a baseline test prior to starting treatment to compare the current results to. This will give a clear picture on what changes have occurred since the treatment plan for the pain started. In many cases of Previcox toxicity a hospital stay will be required to monitor the patient’s liver and kidney functionality.

Treatment for acute NSAID poisoning, such as you would see from a single large overdose of Previcox, generally starts with your veterinarian instigating vomiting in the patient or possibly gastric lavage, also known as gastric irrigation. This procedure is usually done under general anesthesia and is done to remove as much of the medication from the digestive system as possible before it can be absorbed into the blood. Activated charcoal should be administered after the stomach contents are removed to prevent reabsorption of any toxin remaining in the system. Any supportive treatment that is required will be administered at this time as well. This can include IV fluids, pain medication, and gastroprotective medications. Adequate fluids are particularly essential to the patient’s healing as the potential for renal failure can be aggravated by even mild dehydration. Prognosis of this condition is dependant on the amount eaten, the speed of initial diagnosis and treatment, and the size of the dog.

Once your pet has returned home from the hospital a calm and quiet environment to recuperate in will help ensure a speedy recovery. Patients recovering from anesthesia may have difficulty with muscle control and coordination when they first get home, and they are often seriously disoriented. Isolation from other pets and from children is often wise until the anesthesia has fully cleared your companion’s system. It is also vital that fresh water be available for your dog at all times as even minor dehydration has a good chance of causing more difficulty. Any medications that were prescribed by your veterinarian should be given as directed. Dogs diagnosed with Previcox overdose will likely need several follow-up appointments to check their liver and kidney function.