Why is Prescription Dog Food More Expensive Than Regular Dog Food?

Sometimes a dog has a condition for which a veterinarian will recommend a specific diet. Maybe the dog has a tendency to develop bladder stones, or suffers from kidney disease, or is allergic to certain ingredients commonly found in pet food and therefore needs special kibble, and the doctor advises that a particular food can mitigate symptoms or even help slow the course of the disease.

You’re all for keeping your dog healthier, or at least more comfortable, so you want to feed him that special food. The rub is that it’s available only at the doctor’s office by prescription — and is significantly more expensive than dog food available at the supermarket.

Have you ever felt suspicious about this? A lot of people have. In fact, a few months ago, a class-action lawsuit was filed in California claiming that some major pet food manufacturers and retailers have been conspiring in a price-fixing scheme by allowing some of their food products to be sold only by veterinarians and thereby raising their prices to levels above fair-market value. Have pet food companies and veterinarians been in profit-making collusion?

Just what does it mean to be a food sold only by prescription?

Foods sold only by veterinarians are by definition prescription diets, and that’s how they’re generally thought of by consumers. But they’re not allowed to be called that by most companies. They must be called therapeutic diets because the term “prescription diet” is trademarked by Hill’s for its own kibble that it makes available through veterinarians only.

Whatever term you use in your head to think of these foods, they are an anomaly in the regulatory world of the U.S. Food and Drug Administration (FDA). That agency specifically prohibits the sale of foods intended to “cure, mitigate, treat, or prevent disease.” Products that make such claims are considered drugs, not foods, and must undergo a costly, complex, multi-year process before being granted approval for sale to the public. The one big exception to this rule is therapeutic diets sold by veterinarians.

How does the FDA get around its own regulation and allow therapeutic diets to be sold as agents to help treat disease? Tufts veterinary nutritionist Cailin Heinze, VMD, DACVN, explains it as follows. Therapeutic diets do in general undergo extensive testing to prove their efficacy before reaching the marketplace, just not to the same degree that would be necessary for them to be sold as drugs. To close the gap in testing, the federal agency requires that therapeutic foods be purchased through, or with the permission of, veterinarians. “In this manner,” Dr. Heinze writes on the Tufts Petfoodology website (vetnutrition.tufts.edu/petfoodology), “they are allowing veterinarians to weigh the evidence and decide which foods to recommend for which pet and making them responsible for monitoring the pets that are eating these diets.”

Why does a veterinarian need to be involved? Consider that some therapeutic diets have nutrient levels that are appropriate for treating certain diseases but could be unsafe for healthy pets. A diet designed for a dog with kidney disease is a perfect example. Such a food will generally be lower in protein than the level recommended for healthy dogs, Dr. Heinze says, and may also have too little phosphorus for a dog whose kidneys are functioning at full throttle. The upshot: the veterinarian has to weigh the course of the disease against typical nutrient requirements and make a decision from there. It also falls to the vet to keep the diet out of the hands of people whose dogs do not have kidney disease so they won’t end up with nutrient deficiencies. That can’t be done from the supermarket or pet food store aisle.

Veterinarians also need to be involved because sometimes a therapeutic diet doesn’t do what it is meant to do, necessitating that the dog be monitored and treated accordingly. For example, diets to prevent recurrence of bladder stones are not always effective. When they don’t work, the stones can block urine flow and cause life-threatening disease. A doctor needs to assess the food’s efficacy in a dog — by periodically checking him for stones — to keep him safe.

But why are therapeutic diets so expensive?

So why are you paying so much more for therapeutic diets than for dog foods you can simply add to your grocery list? After all, while proportions of ingredients may differ, the ingredients themselves are largely the same as in typical food for healthy pets. Is it the professional expertise of veterinarians that drives up the cost? Is it the fact that people with sick dogs are “stuck” and need to choose therapeutic diets, thus making it all too easy for manufacturers to price gouge? Or some combination of the two, leading to a secret handshake between veterinarians and pet food companies that benefits both sides?

The answer is none of the above. It’s in the testing that eventually brings these foods to market. Granted, that testing is not as arduous as testing for drugs, as we explained above. But it is still extensive. Consider food for kidney disease. Explains Dr. Heinze, “examples of testing for kidney diets includes feeding the diets to pets with kidney disease for many months and monitoring how they do compared to pets fed more typical diets. This requires lots of bloodwork and other diagnostics. For diets for bladder stone prevention, the diets are fed to animals, their urine is collected and tested and the diet ingredients are then optimized to reduce risk of stone development.”

Extra work also goes into analyzing the fiber content of dog food meant for pets with certain gastrointestinal conditions. And therapeutic diets designed for dogs with food allergies have to contain bits of protein divided into small enough molecules so as to evade the immune system and thereby not trigger an allergic reaction.

“As you can probably imagine,” Dr. Heinze says, “all of this testing can get VERY expensive — costing hundreds of thousands of dollars per diet, and these tests often need to be repeated every time there are any changes made to the diet. These costs must then be incorporated into the cost of the diets.”

In other words, it’s not a get-rich scheme for pet food manufacturers or veterinarians. It’s that the science that goes into putting these diets together is expensive. Indeed, Dr. Heinze states emphatically, “vets are not getting rich selling pet food.” To the contrary, the mark-up on therapeutic diets is typically less than that of most regular pet diets because veterinarians do not look at them as revenue generators; they stock these diets rather as a convenience to their clients. If they want, pet owners can generally purchase these foods online or at pet food stores with a prescription, just as many veterinary drugs can be purchased from an outside pharmacy.

The FDA Guidelines on Therapeutic Pet Food Compliance

While therapeutic diets are supposed to be sold to dog owners by veterinarians only, a number of new companies have begun to market them directly to consumers, both in stores and online, running afoul of the regulation. “This shift toward direct marketing, without veterinary direction or involvement, concerns FDA,” the agency has said in a press release, “because these diets…may not be suitable for all pets.”

To clarify its position and put teeth into its ruling, the Food and Drug Administration has come out with a Compliance Policy Guide. The compliance guide explains the criteria FDA will consider when determining whether to take enforcement action regarding dog and cat food diets intended to treat a disease. The agency does intend “to exercise enforcement discretion over the labeling and marketing of these diets,” it states.

Implications of the Lawsuit

Because of the specifics of the FDA guidelines, it is doubtful that the plaintiffs in the class-action lawsuit will prevail. And from the point of view of dogs’ health, that is all to the good. If the prices of therapeutic diets were forced down legally, pet food companies would no longer be able to afford the research required to develop them, and they would therefore discontinue bringing them to market.

If your veterinarian ever recommends a therapeutic diet for your dog, ask why the diet is necessary and how it will help your pet cope with the condition for which he has been diagnosed. Ask, too, what makes the diet different from a diet you would be able to purchase at the store. That way, you will feel good about your decision, knowing you’re doing what you can for your dog rather than following the doctor’s advice but potentially feeling distrustful as you do so.