Are veterinary drugs better for pets?
Are veterinary drugs better for pets?
Last weekend, one of my patients developed an acute and uncomfortable bladder infection. Since it was the weekend and the pet dispensary was closed, the owner requested I call her local pharmacy for the human version of the dog antibiotic that had successfully treated the bladder infection in the past. Although human drugs are not tested in pets, and you should NEVER give your pet human medication without consulting your veterinarian, in this instance I was able to prescribe a liquid antibiotic formulated for children that could be dosed appropriately for the dog as a stopgap measure. Medicating a pet with drugs from a human pharmacy is not always the best plan however, and I’ll explain why below.
The Difference Between Medications for Humans and Animals
Like human drugs, medications made specifically for dogs and cats are approved for use by the Food and Drug Administration based on scientific studies documenting the drug’s safety and efficacy. FDA approval assures pet owners and veterinarians the medication will have a reasonable chance of help the pet recover from their illness. However, there are differences in the way the medications are packaged and delivered. In the example above, the liquid form of the human drug gives me flexibility in dosing, which is not available with pills. Human pills are often far too large in size and dose for small dog and cat patients.
There are also differences in flavor. The antibiotic liquid in our example is a sweet cherry flavor to entice young children to take their spoonful of medicine. But dogs and cats are not big fans of cherry syrup flavoring. The owner struggled to medicate the dog until she could come to AMC for the beef-flavored, animal version of the medication. Companies manufacturing dog and cat medications take palatability into consideration during the manufacturing process. But there is an obvious risk to this approach: according to the ASPCA Animal Poison Control Center, about 10% of ingested toxins can be chalked up to an overindulgence of veterinary medications.
Differences Between Human and Animal Physiology
Even though we ascribe many human personality traits to our pets, their physiology is not exactly the same as ours. Drug metabolism is unique to each species, and human drugs are not necessarily compatible with dogs and cats. Take for example the antibiotic ciprofloxacin. This antibiotic is commonly available at human pharmacies and is a cousin to the veterinary medication enrofloxacin. In dogs, enrofloxacin is metabolized to ciprofloxacin, and intuitively it seems ciprofloxacin would be a good antibiotic choice. Not so. The generic version of ciprofloxacin available at a human pharmacy has variable absorption in dogs and may not achieve therapeutic levels in the bloodstream.
Another concern with human medications is those that contain xylitol. Xylitol is extremely toxic and potentially fatal to dogs. Oral liquids, such as children’s Allegra Oral Suspension, some cough drops, sugar-free medicated gummies and a whole host of mediations intended for humans contain xylitol. Veterinarians must be careful not to prescribe xylitol-containing medication for dogs. For a full list click here.
Human Medications Used in Animals by Necessity
Sometimes veterinarians have no other choice but to use human medications for their patients. I checked with AMC’s Avian and Exotic Pet Service, and they report that very few drugs have been approved by the FDA for use in these special pets. One exception is the Suprelorin F implant, which is approved to treat adrenal gland disease in ferrets. Veterinary oncology is similarly lacking in pet-specific drugs. There are no approved drugs to treat cancer in cats, and there are only four drugs approved for dogs with mast cell tumors and lymphoma. This dearth of FDA-approved drugs for avian and exotic pets and pet cancers leaves those specialists to adapt human drugs for use in veterinary patients, as allowed by government regulations.
Veterinarians understand the convenience of medications from the corner drugstore, but keep in mind, they may not be a good a substitute for the veterinary product. An extra trip to the veterinary clinic may be required to pick up the optimal medication for your pet.