Cushing’s Disease in Dogs: Recognizing the Signs and Testing Right

In brief

There are five things you should know about Cushing’s syndrome. First: it is caused by a persistent excess of cortisol—and because cortisol acts everywhere, it affects thirst, coat, muscles, liver and immune system all at once. Second: among the most common and most noticeable early signs are increased drinking and urination—and you can measure that at home before a lab is involved at all. Third, and this is the key sentence: Testing is done only when the clinical picture fits. The international expert panel states this explicitly—in dogs without a matching clinical suspicion, the proportion of false-positive results rises considerably. Fourth: No test proves Cushing’s. All common procedures have error rates in both directions, and many other diseases distort them. Fifth: treatment is effective, but not harmless—it has to be monitored closely.

Cushing’s is a disease in which the road to a diagnosis can itself become the problem. This article explains how to recognize it, why testing without a suspicion does more harm than good, and what treatment can achieve.

Note: This article is general information and does not replace a veterinary examination. A Cushing’s treatment that has been started is never changed or stopped on your own.

👉 Prevention and health at a glance: Dog Health Basics

1. What happens in Cushing’s

The adrenal glands sit in front of the kidneys and produce, among other things, cortisol—a vital hormone that regulates blood sugar, dampens inflammation and adjusts the body to stress.

In Cushing’s syndrome, too much of it is released over a long period. Cortisol is essentially the body’s own cortisone, and the consequences resemble those of years of cortisone treatment: muscle wasting, thin skin, fat shifting into the abdomen, a suppressed immune system, thirst and the urge to urinate.

There are three possible causes:

The pituitary form accounts for the vast majority of cases. A small, usually benign tumor of the pituitary gland releases too much of a controlling hormone and thereby drives both adrenal glands.

The adrenal form is caused by a tumor on one adrenal gland itself, which produces cortisol on its own.

The medication-induced form results from prolonged cortisone use—as a tablet, an injection, an ointment or even eye drops. It is the only form that can resolve when the drug is stopped, and it is often overlooked because nobody thinks the ointment matters.

This three-way split is more than classification; it determines what happens next. The pituitary form is, as a rule, treated with lifelong medication. An adrenal tumor raises the question of surgery. And the medication-induced form needs no Cushing’s treatment at all, but a careful tapering of the drug that triggered it—under veterinary guidance, because stopping abruptly is dangerous.

That is why every workup begins with a question that costs nothing: which medications is this dog getting—all of them, including ointments, ear and eye drops, and whatever was prescribed months ago and is still in the cupboard?

2. How to recognize it

The signs creep in and are often put down to age.

• Increased drinking and urination—one of the most common and often the earliest signs, frequently with needing to go out at night or accidents in the house
• Ravenous appetite: the dog begs, steals, raids the trash—behavior you have never seen before
• Pot belly combined with thinning legs and wasted back muscles
• Coat changes: symmetrical hair loss on the flanks, thin skin, poor wound healing, recurring skin infections
• Panting, even at rest and in cool temperatures
• Muscle weakness, trouble jumping and climbing stairs
• Lethargy and less interest

Here, too, the combination is what counts. An old dog who drinks a bit more is not a case. A dog who drinks more and is ravenous and develops a pot belly and loses coat is one.

👉 When skin and coat are the main issue: Itching in Dogs

2.1 Cushing’s or just old age?

“It’s just age” is the most common misreading of this condition—and it is not foolish but understandable, because several signs genuinely overlap. Three distinctions help.

The direction. An aging dog slows down overall, tends to eat less rather than more, and declines evenly. In Cushing’s, things pull apart: appetite rises while muscle mass falls, and the belly grows while the legs get thinner. This opposing movement is not part of normal aging.

The pace. Age-related changes take years. A dog whose water intake, coat and belly shape change within months is not simply aging—there is probably an illness behind it.

The combination. Every single sign has a harmless explanation. With four of them at once, a harmless explanation becomes unlikely. That is why section 2 gives a list rather than one key symptom.

And an observation from counseling that comes up again and again: with Cushing’s, owners often report behavior changes they cannot explain—a dog who suddenly raids the trash or steals food although he has never done so before. Ravenous hunger of this kind is not a sign of age and not a training issue.

3. The most important clue often comes from you

This is the most practically valuable part of the article, and it costs nothing.

Increased drinking is one of the most common early signs—but “he’s drinking more” is worthless as information, because the impression is deceptive. Measure it.

Here is how: in the morning, fill the bowl with a measured amount of water, measure everything you top up over 24 hours, and at the end measure what is left. With several dogs or water from other sources it becomes imprecise—then measure on several days and note the circumstances. Keep this up for three to five days and calculate the average.

As a rough guide, a repeatedly measured intake of more than about 100 milliliters per kilogram of body weight per day is considered abnormal. The key word is repeatedly: a hot summer day, salty food or a long walk fully explain a single high value. A 20-kg dog who consistently drinks more than two liters over several quiet days, on the other hand, needs to be checked.

That number on a piece of paper fundamentally changes the conversation at the clinic. It turns an impression into a solid clue—and at the same time it is the basis for deciding whether testing should happen at all.

4. What else makes a dog drink a lot

Because increased thirst is the leading symptom, the alternatives belong here too—and there are more of them than most people assume.

Diabetes mellitus. Also thirst, frequent urination and ravenous appetite—but typically with weight loss instead of a pot belly. Incidentally, the two not uncommonly occur together, because Cushing’s favors the development of diabetes.

Chronic kidney disease. The classic in older dogs, often with weight loss, vomiting and a poor coat.

Uterine infection (pyometra) in intact females—increased thirst a few weeks after a heat is an alarm sign here and an emergency.

Liver diseases as well as calcium and electrolyte disorders.

Medications, above all cortisone and diuretics—the latter are standard for heart patients.

And simply behavior: some dogs drink more in the heat, after salty food or out of boredom.

That is exactly why the measured water intake is the beginning of the workup, not its end—it tells you that something is going on, but not what.

5. Why testing is done only on suspicion

This is where Cushing’s differs from most other diagnoses—and the international expert panel puts it unusually clearly: Hormone tests should be performed only when there are signs consistent with Cushing’s.

The reason is not thrift but arithmetic. What a test result means depends not only on the test, but on how likely the disease was beforehand. If you test a group in which many actually have Cushing’s, positive results are mostly correct. If, on the other hand, you test a dog for whom nothing really points to it, the false-positive results outnumber the true ones—simply because there are so many more healthy dogs than sick ones.

On top of that, no test is perfect. With the ACTH stimulation test, for example, depending on the study, the test falsely comes back positive in 7 to 41 percent of dogs without Cushing’s—specificity lies between 59 and 93 percent, sensitivity between 57 and 95 percent depending on the form. The low-dose dexamethasone suppression test is more sensitive—85 to 100 percent—but with it, too, there is no cutoff that catches every case.

That is exactly why there is a step that often comes before any blood test and that many owners don’t know about: the urine cortisol-to-creatinine ratio. The morning urine is collected at home, on several days—no car ride, no waiting room, no blood draw. That matters because stress raises cortisol levels and can distort a test done at the clinic.

Its strength lies in ruling things out: if the value is normal, Cushing’s is very unlikely, and further tests are usually unnecessary. If it is elevated, on the other hand, that proves nothing—other diseases and stress raise it too. Then the specific blood tests follow.

That makes it a sensible first step: inexpensive, stress-free and good at answering the question of whether there is any need to keep looking.

One limitation belongs here, though, because otherwise it would contradict the key message of this section: this test is not a screening test for just any dog either. It is used when a suspicion already exists—that is, when the clinical picture from section 2 fits. In a dog without signs, the same problem applies to it as to all other procedures: elevated values have many causes, and without a prior suspicion the false-positive results would outnumber the true ones.

So its advantage is not that it may be used without a suspicion, but that, when a suspicion exists, it offers the least stressful and least expensive way in.

And finally: No single lab finding is proof. Neither elevated liver values nor dilute urine nor an abnormal blood count—they all fit Cushing’s, but they occur just as often with many other things.

This leads to the order that makes all the difference: first the picture, then the test. Not the other way around.

5.1 The three procedures side by side

Because clinics work with abbreviations, here is what each of the three common procedures does and where its limit lies.

The urine cortisol-to-creatinine ratio. Collected at home, without stress, inexpensive. It is good at ruling out and poor at proving: a normal value makes Cushing’s very unlikely; an elevated one only says that the search has to continue.

The low-dose dexamethasone suppression test. The more sensitive of the two blood tests—it misses a true case less often. In exchange, it takes eight hours with several blood draws, and it is easily affected by other diseases and by stress.

The ACTH stimulation test. Quicker and simpler to perform, but less sensitive—it misses some of the cases. Its real strength lies elsewhere: it is the procedure used to monitor treatment, and it detects the medication-induced form.

Which procedure is used when is decided by the clinic based on the question at hand—initial workup, telling the forms apart, and monitoring therapy are three different questions for three different tests.

What applies to all three: no result is read in isolation. The finding is brought together with the clinical picture, and if the two don’t match, that is a reason to pause—not to treat.

6. Collecting morning urine at home

The urine cortisol-to-creatinine ratio from the previous section is the least expensive and least stressful first step—and it regularly fails because nobody explains how to get hold of the urine. So here it is, in concrete terms.

6.1 Why at home and why in the morning

The decisive point is the absence of stress. A car ride, a waiting room and strangers’ hands raise cortisol levels—and that is exactly what the test is meant to measure. A sample taken at the clinic can therefore be elevated without Cushing’s being present.

The morning urine is the first portion after the night’s rest. It is the least influenced by the day’s events and the most comparable. It is collected on several consecutive days—how many is decided by your veterinary clinic.

6.2 How to do it in practice

With males, a flat ladle or a shallow cup on a stick, held to the side, works well. Keep a bit of distance and stay calm—many males stop when someone stands right next to them.

With females, a shallow dish is the tool of choice, slid under the dog from behind as soon as she squats. An aluminum soup plate or a flat lid helps—deep containers bother most females.

In both cases: practice once beforehand, on a day when the sample isn’t needed. A dog who gets startled on the first attempt will stop as early as the preparation on the second.

6.3 What spoils the sample

The container must be clean and free of dish soap residue—rinsing with clear water is enough; dish soap is not. Urine soaked up from the floor is unusable, as is urine from snow or grass.

The sample should go to the clinic chilled and promptly. If it stands at room temperature for several hours, its components change. A container from the clinic is better than a jam jar.

And write the time and date on the container. When collecting over several days, that is the information the evaluation depends on.

7. The trap: the elevated liver value

One pattern that leads people astray time and again at the clinic deserves a mention of its own.

In Cushing’s, alkaline phosphatase is typically markedly elevated, listed in the lab report as ALP or ALKP—cortisol stimulates a separate form of this enzyme. As a result, an incidentally abnormal ALP on a routine panel gets read as a suspicion of Cushing’s and a test is triggered, even though the clinical picture is missing.

Yet this very value is often elevated in isolation in older dogs, without any disease significance—among other things because of benign nodular changes in the liver that increase with age.

This is exactly the case the expert panel warns about. Elevated liver values have many causes: medications, other liver diseases, dental inflammation, obesity, benign age-related changes. They are a reason to keep looking—but not a reason to test specifically for Cushing’s if the dog is neither drinking more nor losing coat nor showing anything else.

The question you can ask at this point is the same as with the thyroid value: Was the test triggered because the picture fits—or because a value stood out?

👉 The same pattern with the thyroid: Hypothyroidism in Dogs

8. What distorts the results

As with the thyroid, there are confounding factors, and they are the main reason for false-positive results.

Other diseases. Numerous diseases that do not involve the adrenal glands can influence the results of adrenal function tests. A dog who is sick with something else is a poor candidate for a Cushing’s test.

Stress. The clinic visit, the car ride, the blood draw—all of this raises cortisol.

Medications. Cortisone in any form is the obvious case. Less well known: anti-seizure drugs can also influence the results; the expert panel recommends particular caution when interpreting them in such patients.

A practical side note that differs from humans: dogs have no daily rhythm of cortisol secretion. The time of the blood draw therefore doesn’t matter as much as it does in human medicine.

👉 Why this matters for epileptic patients: Epilepsy in Dogs

9. Imaging: what it can and cannot do

Ultrasound of the adrenal glands is an important building block, but it has a clear limit: it can neither prove nor rule out Cushing’s.

What it does achieve is telling the forms apart. If both adrenal glands are evenly enlarged, that points to the pituitary form. If one is markedly enlarged and the other shrunken, that points to an adrenal tumor—and that fundamentally changes the treatment.

What it does not achieve: Normal-looking adrenal glands do not rule out Cushing’s. And conversely, enlarged adrenal glands alone are not a diagnosis.

If an adrenal tumor is suspected, further procedures are added to assess whether surgery is an option.

10. Which dogs are affected

Cushing’s is a disease of the older dog—onset is typically beyond the age of six, often considerably later. In a young dog the diagnosis is very unlikely and should be examined especially critically.

Breeds affected more often than average include poodles, dachshunds, boxers, beagles, Yorkshire terriers, miniature schnauzers, Jack Russell terriers and Boston terriers. The pituitary form mainly affects small to medium-sized breeds, while adrenal tumors occur more often in larger dogs.

Important for context: the combination of advanced age and typical signs raises the probability considerably—and with it, as described above, the meaningfulness of a positive test result. So age and breed are not just background information here but part of the calculation.

11. What else comes with it—and when treatment happens at all

11.1 Cushing’s rarely comes alone

A persistent excess of cortisol acts on so many systems that secondary problems develop—and at the clinic these are sometimes treated separately without anyone making the connection.

Diabetes mellitus. Cortisol counteracts insulin. Cushing’s therefore favors diabetes, and diabetes that can’t be properly regulated is a reason to think of Cushing’s.

Urinary tract infections. In these dogs they often run without the typical signs, because the suppressed immune system weakens the inflammatory response. So a dog who suddenly has accidents in the house isn’t necessarily “just” thirstier.

High blood pressure. It often causes no symptoms and is therefore only found if it is measured.

Skin problems. Thin skin, poor wound healing and recurring infections are a consequence, not a coincidence—and they often improve only once the underlying problem is treated.

In practical terms: if you are at the clinic because of one of these issues and can at the same time tick off the signs from section 2, actively bring up the connection.

11.2 Not every diagnosis leads straight to treatment

This surprises many people, but it is a serious weighing-up. Treatment suppresses cortisol production, it is lifelong, it costs money, it requires regular monitoring—and, as section 13 shows, it can tip over in the other direction.

A dog with clear problems argues for starting promptly: massive thirst, accidents at night, muscle wasting, recurring infections. Here, treatment noticeably improves quality of life.

The weighing-up may come out more cautiously for a very old dog with mild signs and relevant concurrent diseases, in whom the burden of monitoring and the risk of overdosing outweigh the expected benefit.

Your veterinarian makes this decision together with you, and it is not a one-time decision—a dog for whom the decision today is to wait may need treatment in six months. That is exactly what the measured water intake from section 3 is for: it is the parameter for tracking the course.

12. Treatment

Treatment is, as a rule, with medication. The drug used suppresses cortisol production—so it does not remove the cause but throttles the effect. That is why the treatment is lifelong.

With an adrenal tumor, surgery may be an option, which—unlike the medication—can cure. It is demanding and is performed at specialized centers.

Two practical points about managing treatment that many owners don’t know.

The timing of the monitoring blood draw is crucial. The commonly used drug trilostane works only over part of the day, and the check has to fall within a specific window after the dose—usually a few hours afterward. If you come at the wrong time or forgot the morning tablet, you get a result that says nothing. So always ask exactly when the tablet should be given and when you need to be there—and say so if something went differently.

Some dogs do better with two smaller doses. Instead of one large dose in the morning, the amount is then split into two doses about twelve hours apart. This evens out the effect over the day and can reduce both evening slumps in energy and side effects. If your dog fluctuates over the course of the day during treatment, that is worth mentioning.

What you should know about the course: The signs recede at different speeds. Water intake and ravenous appetite often improve within weeks. Muscles and coat take months—for the coat, not infrequently six months or longer, and sometimes some of it remains.

And a point that adjusts expectations: The goal is a dog who is doing well, not a lab value in the target range. Dose adjustment is guided largely by how the dog is doing in everyday life—water intake, appetite, activity—not by the number in the report alone.

12.1 The monitoring appointments—why so many, and what for

Anyone who starts Cushing’s treatment also starts a series of appointments. That surprises many people and is sometimes felt to be excessive—so here is what they are for.

In the first weeks, the goal is to find the dose. The drug suppresses cortisol production, and how strongly it does so in a particular dog cannot be calculated in advance. Too little doesn’t work; too much tips into the opposite direction described in section 13—and the way there is short.

That is why monitoring is close at the start, then at longer intervals, but it continues for good. A dog who has been stable for two years still needs checkups: the underlying process can change, and the right dose today is not necessarily the right dose two years from now.

What comes together each time is always both—a lab value and your report. That is why the three details from section 14 are so important: water intake, appetite, activity. For finding the dose they are at least as informative as the number, and they are the only information that arises between two appointments.

A practical tip that saves appointments: before every checkup, write down the current water intake over three days. That puts a solid figure on the table instead of “I think it’s gotten better”—and that is exactly what determines whether the dose is adjusted or not.

12.2 What can be said about the prognosis—and what can’t

This question comes up in every consultation, usually first. An honest answer has to separate three things.

The form plays a part. In the pituitary form, which makes up the vast majority, the cause is a small, usually benign tumor of the pituitary gland. It is not the tumor that is treated but its effect—and in many dogs that works for years. With an adrenal tumor, the outlook depends on whether it is benign or malignant and whether surgery is an option; here the range is considerably wider.

Age puts the numbers in perspective. Cushing’s is a disease of the older dog. A ten-year-old with well-controlled Cushing’s statistically often dies of something else—that is not a euphemism but the reason why bare survival figures are hard to interpret for this disease.

Quality of life is the more meaningful measure. What reliably improves under treatment are exactly the things that weigh on everyday life: thirst, needing to go out at night, ravenous appetite, panting. Muscles and coat take longer, and some of it may remain.

What we deliberately do not give are concrete survival times. The figures in circulation come from different patient groups with different starting points, and a number without that context is falsely precise. For the individual dog, the question is a different one anyway: how is he doing with treatment, and how would he be doing without it?

13. When treatment tips over

This is the part every owner of a treated dog needs to know.

Treatment throttles cortisol production—and it can throttle it too far. Then the opposite of Cushing’s develops: a deficiency that can become life-threatening.

The warning signs are nonspecific, and that is exactly what makes them dangerous:

• Loss of appetite or complete refusal of food
• Vomiting and diarrhea
• Marked weakness, trembling, staggering
• Listlessness

The rule is simple and not negotiable: With these signs, the medication is stopped and the clinic is contacted immediately—not after waiting for the next dose, not on Monday. A dog on Cushing’s treatment who isn’t eating is an emergency until proven otherwise.

What then happens at the clinic is not guesswork but a targeted workup: it is checked whether there has been an overdose and whether this has led to a deficiency of the adrenal cortex—through blood values and usually an ACTH stimulation test. The same signs can also have a completely different cause, such as a gastrointestinal infection; that is exactly why the dog is examined rather than guessed at.

This changes nothing about what you do: stop and call. The clinic makes the distinction, not you—and it cannot be made without an examination anyway.

That is exactly why the monitoring appointments in the first weeks are so closely spaced, and why it pays to go through these signs with everyone in the household.

14. What you can do at home

Measure water intake, before the diagnosis and after. It is one of the best parameters for tracking the course that there is—better than any impression and available to you at any time.

Photograph the belly and bald patches from the same distance and in the same light. Otherwise you won’t see changes over months.

Note appetite, activity and needing to go out at night. These three details guide the dose more than most owners realize.

List all medications, including ointments, ear and eye drops containing cortisone. They are a frequently overlooked cause.

Go through the warning signs with your household, so that someone else will react correctly too.

Never change the dose on your own—but do pause the medication and call if your dog isn’t eating.

👉 What changes with age anyway: Caring for a Senior Dog

15. Limits of the evidence

The test figures come from different studies with different reference standards, cutoffs and patient groups—hence the wide ranges. They show the order of magnitude and the direction, not exact values for a particular lab.

There is also a fundamental problem: for Cushing’s syndrome in the living dog there is no true gold standard. Every evaluation of a test therefore compares it with a combination of clinical picture and other tests—which makes the figures less robust than they look.

A chapter of its own is so-called atypical or occult Cushing’s: the idea that it is not cortisol but its precursors or sex hormones from the adrenal gland that cause the picture, while the usual tests stay normal. The term circulates in dog circles more often than its evidence base warrants: the consensus explicitly states that the role of cortisol precursors and sex hormones in this picture remains unclear—and only some of the expert panel test for it at all, and then only once all other explanations have been ruled out. So the term is not a suitable explanation for a dog in whom nothing else has been found.

The consensus cited dates from 2013. Its core messages—test only when the picture fits, no test is perfect, other diseases distort the results—remain valid; individual cutoffs and procedures have evolved since.

And the guide value of about 100 milliliters per kilogram per day is a clinical rule of thumb with some leeway: feeding, temperature and activity influence water intake considerably.

And a note on the sources behind this article: at its core it relies on two consensus papers and one review. Consensus papers are agreed expert opinion based on the available literature—the best framework available for a disease without a gold standard, but still a framework and not a randomized trial.

16. Conclusion

Cushing’s is caused by a persistent excess of cortisol and therefore shows up everywhere at once—in thirst, coat, muscles, belly size. The most important clue often comes not from the lab but from you: a water intake measured over several days turns an impression into a reason to act. And that is exactly what matters, because a rule applies here that the expert panel states explicitly: Testing is done only when the picture fits. If a hormone test comes back positive in a dog without matching signs, the result is more often false than true—and a false result can turn into lifelong treatment. If the diagnosis is solid, on the other hand, treatment is effective. It only requires you to know one warning sign: A dog on Cushing’s treatment who isn’t eating needs to go to the clinic immediately.

👉 What matters when choosing: Choosing a Good Veterinarian

If you take away just one thing: measure water intake before you do anything else. It costs nothing, it helps decide whether testing should happen at all, and afterward it remains the best parameter you have for tracking the course.

Key takeaways on Cushing’s syndrome

First the picture, then the test. The international expert panel states this explicitly: hormone tests belong only with dogs that show matching signs. If testing is done without a suspicion, false-positive results outnumber true ones—simply because there are many more healthy dogs than sick ones.

No test proves Cushing’s. With the ACTH stimulation test, depending on the study, the test falsely comes back positive in 7 to 41 percent of dogs without Cushing’s; with the low-dose dexamethasone suppression test there is no cutoff that catches every case.

The measured water intake is the owner’s most valuable contribution. “He’s drinking more” is worthless; a number isn’t. As a rough guide, repeatedly more than about 100 milliliters per kilogram per day is considered abnormal—the key word is repeatedly.

The urine test is the least stressful first step. Its strength lies in ruling out: a normal value makes Cushing’s very unlikely; an elevated one proves nothing.

An isolated elevated alkaline phosphatase is not a suspicion. In older dogs it is often elevated without any disease significance—and still regularly triggers tests even though the clinical picture is missing.

Ultrasound tells the forms apart; it does not diagnose. Normal-looking adrenal glands do not rule out Cushing’s; enlarged ones alone are not a diagnosis.

A frequently overlooked cause is cortisone from outside—as a tablet, injection, ointment or eye drops. It is also the only form that can resolve when the drug is stopped.

A dog on Cushing’s treatment who isn’t eating is an emergency. With loss of appetite, vomiting, weakness or listlessness, the medication is stopped and the clinic contacted immediately—not after waiting for the next dose.

The goal is a dog who is doing well, not a lab value in the target range. Water intake, appetite and activity guide the dose more than the number in the report.

References

• Behrend, E. N., Kooistra, H. S., Nelson, R., Reusch, C. E. & Scott-Moncrieff, J. C. (2013): Diagnosis of spontaneous canine hyperadrenocorticism: 2012 ACVIM consensus statement (small animal). Journal of Veterinary Internal Medicine 27(6): 1292–1304. https://doi.org/10.1111/jvim.12192 (suspicion arises from history and clinical examination; hormone tests only with matching clinical signs; no screening or differentiating test is error-free; no lab finding is diagnostic; ACTH stimulation test with sensitivity 57–95% and specificity 59–93%, low-dose dexamethasone suppression test with sensitivity 85–100% but specificity of only 44–73%; positive and negative predictive values depend on disease prevalence in the tested group; caution in dogs on anti-seizure drugs; dogs show no daily rhythm of cortisol secretion)
• Bugbee, A., Rucinsky, R., Cazabon, S., Kvitko-White, H., Lathan, P., Nichelason, A. & Rudolph, L. (2023): 2023 AAHA Selected Endocrinopathies of Dogs and Cats Guidelines. Journal of the American Animal Hospital Association 59(3): 113–135. https://doi.org/10.5326/JAAHA-MS-7368 (ACTH stimulation test with false-negative results in up to 41% of dogs with an adrenal tumor; up to 35% of dogs with the pituitary-dependent form meet no suppression criterion in the dexamethasone suppression test; dexamethasone suppression test as the screening test of choice, ACTH stimulation test to confirm iatrogenic Cushing’s; no endocrine testing within two weeks of short-acting and four weeks of long-acting glucocorticoids)
• Bennaim, M., Shiel, R. E. & Mooney, C. T. (2019): Diagnosis of spontaneous hyperadrenocorticism in dogs. Part 2: Adrenal function testing and differentiating tests. The Veterinary Journal 252: 105343. https://doi.org/10.1016/j.tvjl.2019.105343 (none of the available adrenal function tests is completely reliable; frequent false-positive and false-negative results; numerous diseases not involving the adrenal glands influence the results)

Frequently asked questions about Cushing’s disease in dogs

What owners ask most often