Vet treating dog

They're either tough to diagnose, expensive to treat, fraught with complications and side effects or just plain baffling — and just about every veterinarian I know dreads them.

I'm talking about 10 diseases that can be a veterinarian's worst nightmare!

Addison's Disease

This is probably on every veterinarian’s top 10 list of tough-to-spot diseases.

The labwork tends to tell you most of what you need to know. In addition to the fact that sodium and potassium levels can be way out of whack, there’s a specific test that can confirm Addison's disease, which affects the adrenal glands in dogs.

But the disease offers such nonspecific symptoms — weakness, vomiting and diarrhea, for example — that many dogs go without adequate treatment, and some can even collapse and die if the adrenal glands aren't secreting the right levels of hormones.

Luckily, it’s highly treatable!

Cushing's Disease

This disease is like Addison’s — in reverse. Cushing's disease manifests as an overabundance of canine adrenal hormones.

It’s generally easier than Addison’s to spot — common signs include increased thirst and urination, a potbelly and skin troubles in most cases — but this one can be a real pain to treat. That’s because most dogs can only be managed with side effect-laden drugs, which is why this disorder tends to rank high on our list of unlikables.

Allergic Skin Disease

In South Florida, allergic skin disease is, by far, the most common dermatologic disorder I encounter in both dogs and cats.

But its prevalence isn't what makes it such a disliked disease — obnoxious effects are more the issue, including itching, redness, hair loss, crusting, ear infections and weeping sores. There's also all the explaining, educating, convincing, cajoling and hand holding it takes to get pet owners to properly understand the disease’s complex ins and outs.

Noise Phobias

For some dogs and their owners, there’s almost nothing worse than the extreme stress associated with serious thunderstorm phobia, but noise phobias come in a close second. Some dogs are so severely affected that veterinarians have no option but to medicate them.

Elimination Disorders

This is arguably one of the most entertaining medical euphemisms in the veterinary lexicon. What "elimination disorder" means is that your pet is urinating and/or defecating in the wrong spots, which is definitely not entertaining for you — or your veterinarian.

Vets hate this disorder because we know how frustrating it can be to live with one of these patients, but also because there’s a challenging list of underlying problems we have to consider as we work toward a solution. The fact that so many of them are tough-to-treat behavioral issues makes this problem all the more annoying.

Feline Idiopathic Cystitis

Talk about frustrating! This disease is one common cause of elimination disorders in cats. Its recurrent nature, combined with the fact that affected cats are truly uncomfortable — and males may even succumb to life-threatening urethral obstructions as a result of the disorder — means it’s both frustrating and scary.

Intervertebral Disk Disease

Dogs affected by severe forms of this disease are not only in serious pain, but they can also be paralyzed. Although it’s potentially treatable — my dog, Vincent, has improved a lot since his surgery for the condition — it’s expensive, thanks to diagnostic tests like CT scans and the need for highly specialized surgical skills. As a result, too many of these patients are euthanized, making this an understandably hated disease.

Feline Stomatitis

The continual cycles of severe pain and oral swelling, along with poor long-term treatment options for feline stomatitis, make this highly uncomfortable condition one that we absolutely dread. Affected cats often stop eating, paw at their mouths and drool.

The fact that we don’t know all the things that can cause this chronically intermittent condition is another factor behind its unhappy effect on vets.

We can prescribe drugs to make it go away temporarily, and extracting all the teeth in the vicinity of the swelling is sometimes effective, but the potential side effects of medication and the reliance on drastic dental measures are not fun for the patient, pet owner or veterinarian.


Euthanizing otherwise healthy animals because of unmanageable aggression is the absolute worst part of my job. Luckily, this doesn’t happen too often now that owners know more about socializing their pets and are more willing to seek treatment early on.


You’d think it would be easy to explain to an owner that a fat pet needs fewer calories and more exercise, but this is one area in which owners need lots of explanation, support and patience from their veterinarians.

The fact that so many owners don’t heed our advice is why so many among us sigh deeply when we see a portly pet. Can you really blame us?

Check out more opinion pieces on Vetstreet.

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