Human Medicine for Dogs and Cats? Here's Why It's Potentially Deadly

Man holding a bottle of pills
Think twice before giving your pet human medication. Dr. Patty Khuly has seen too many patients that have become seriously ill or died from ingesting medication.

Among the more important lessons future veterinarians are asked to internalize is one they learn on their very first day of vet school: Every animal species is different. In other words, cats are not small dogs and dogs are not small horses, etc.

You’d think this would be apparent — especially to science-centric thinkers. However, sometimes the most obvious things can prove elusive to those who otherwise think logically.

Take last month’s client. For the sake of his anonymity, I'll just describe him as a highly credentialed human health care worker. Though he’s obviously a smart guy, his high-powered brain tricked him into offering acetaminophen (Tylenol) to his feverish cat. For several days.

Did it do the trick? Maybe for the fever, but we’ll never know. The cat died after her blood was poisoned by the stuff. Chocolate-brown pigment stood in for the bright red of the oxygen-carrying hemoglobin molecule in her red blood cells. She died of an inability to feed her cells oxygen.

It was an accident, of course — one based on logic and assumption — but a tragedy all the same.

Toxins in the Medicine Cabinet

This is a common misjudgment in veterinary medicine: Pet owners assume that over-the-counter medications perceived as relatively "safe" for humans will have the same harmless, pain-relieving effects on other species, such as dogs and cats. It's so common, in fact, that only last week another client arrived with a similar situation. That pet we saved, but not without intensive care, two blood transfusions and a few nights of touch-and-go anxiety — not to mention guilt.

The 15-pound patient had received about eight doses of naproxen (Aleve) over the course of the previous five days. Even one might’ve done him in, but his cast-iron intestines resisted perforation by deep, bleeding ulcers.

Medications like ibuprofen (Advil) and naproxen help certain types of pain in humans, which is why some pet owners assume it's OK to give them to their pets. Trouble is, those medications can kill animals.

Talk to Your Veterinarian First

Though I've been schooled in comparative medicine, I would never presume to give my son a dose of any drug based on my knowledge of how that drug works in cats. Yet plenty of pet owners make similar mistakes, based on presumption, bad advice from the Internet or a conversation with a neighbor over the fence. Unfortunately, well-meaning assumptions about human medications can have devastating results.

So be aware of the top human medications that are toxic to pets. And when in doubt, call your veterinarian before giving your pet any human medicine.

I’ve seen too many tragedies to remain quiet on this subject.

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