Non-Steroidal Antiinflammatories (NSAIDs) are commonly used to treat inflammation, pain and fever. NSAIDs like Ibuprofen and Naproxen (Aleve) that are used in humans are actually toxic to dogs and cats. Ingestion of these drugs can lead to gastrointestinal ulcers and kidney failure.
NSAIDs are absorbed by the gastrointestinal tract and are highly protein bound. About 60-80% of the ingested amount is absorbed in dogs. The mechanism of action is not specifically known but it is thought to inhibit COX 2 enzyme from converting arachadonic acid into prostaglandins. Prostaglandins are important in mediating inflammatory factors in the body. It is also thought to have an effect on COX 1 enzyme which affects the body’s ability to maintain normal gastric mucosal barriers, renal blood flow and platelet aggregation.
Symptoms include vomiting, loss of appetite, bloody vomit, lethargy, diarrhea, dark/black colored stools, decreased urine production and abdominal discomfort. These signs are seen at ingestion doses of 50mg/kg – 175mg/kg. In severe cases (>400mg/kg) we can see affects to the central nervous system with symptoms that include altered mentation, uncoordinated walking and seizures.
Treatment includes inducing vomiting followed by the administration of activated charcoal. In addition to this, hospitalization with fluid therapy and gastrointestinal protectants for 48 to 72 hours is recommended. During this time baseline lab work will be performed (CBC, Chemistry profile, Urinalysis and Urine specific gravity) with repeat kidney values every 24 hours. Severe ingestions can be treated with peritoneal or hemodialysis, but can be expensive.
If you are concerned that your pet may be in pain, please consult your veterinarian before giving him/her any over the counter human pharmaceuticals. There are veterinary specific NSAIDs for dogs and cats (Rimadyl, Metacam) that reduce the toxic side effects attributed with NSAIDs and are more effective in treating their pain.