Addison’s Disease in Dogs: Symptoms, Diagnosis & Lifelong Management

Last updated: May 6, 2026

When a previously healthy dog starts vomiting without explanation, loses interest in food, and seems unusually tired for days or weeks at a time, most owners assume a stomach bug or a passing illness. But when those episodes keep returning — or suddenly escalate into collapse and shock — something far more serious may be at work. Addison’s disease in dogs, also known as hypoadrenocorticism, is a condition where the adrenal glands stop producing enough of the hormones the body needs to function. It is often called “the great imitator” because its symptoms mimic so many other conditions, making it one of the most commonly missed diagnoses in veterinary medicine.

The good news is that once identified, Addison’s disease is highly treatable. Dogs with this condition can live full, happy lives with the right medication and monitoring. Understanding what to look for and how treatment works can make all the difference — sometimes literally saving your dog’s life.

What Is Addison’s Disease in Dogs?

Addison’s disease occurs when the adrenal glands — two small glands that sit just in front of the kidneys — fail to produce adequate amounts of two critical hormone groups: glucocorticoids (primarily cortisol) and mineralocorticoids (primarily aldosterone). Together, these hormones regulate an extraordinary range of body functions including metabolism, blood pressure, electrolyte balance, stress response, immune function, and blood sugar levels.

In most cases, the condition results from immune-mediated destruction of the adrenal cortex — the outer layer of the adrenal glands where these hormones are produced. The dog’s own immune system attacks and gradually destroys the gland tissue. By the time clinical signs appear, roughly 85 to 90 percent of the adrenal cortex has already been destroyed, which is why the onset can seem so sudden even though the damage has been building for weeks or months.

Less commonly, Addison’s disease in dogs can be caused by other factors: certain medications (including the Cushing’s disease drug mitotane, which intentionally destroys adrenal tissue), tumors that infiltrate the adrenal glands, infections, or — rarely — a problem with the pituitary gland that fails to send the signals the adrenals need to function. Abrupt withdrawal of long-term corticosteroid medication can also trigger an Addisonian episode because the adrenal glands, suppressed by the external steroids, have not had time to resume normal production.

Typical vs. Atypical Addison’s Disease

Not all cases of Addison’s disease present the same way, and the distinction between typical and atypical forms is important for both diagnosis and treatment.

Typical Addison’s disease involves deficiency of both cortisol and aldosterone. Because aldosterone is responsible for regulating sodium and potassium levels in the blood, dogs with the typical form show characteristic electrolyte imbalances — low sodium and high potassium. This electrolyte disruption is what makes the condition dangerous, because elevated potassium can slow the heart rate and, in severe cases, cause life-threatening cardiac arrhythmias. The electrolyte pattern is often the first clue that points a veterinarian toward Addison’s rather than other conditions with similar symptoms.

Atypical Addison’s disease involves a deficiency of cortisol alone, with aldosterone production remaining intact. Because the electrolyte values look normal on routine blood work, atypical Addison’s is significantly harder to diagnose. Dogs with the atypical form may be misdiagnosed with gastrointestinal disease, kidney problems, or simply “not doing well” for extended periods before the true cause is identified. It is worth noting that some dogs initially diagnosed with atypical Addison’s eventually progress to the typical form as more of the adrenal cortex is destroyed, developing electrolyte abnormalities later in the course of the disease.

Symptoms of Addison’s Disease in Dogs

The symptoms of Addison’s disease in dogs are frustratingly nonspecific when taken individually. It is the pattern — recurring episodes of illness, symptoms that wax and wane, and a dog that seems to get worse during stressful situations — that should raise suspicion.

Vomiting and diarrhea. Gastrointestinal upset is one of the most common presenting complaints. Dogs with Addison’s may vomit intermittently, have episodes of diarrhea (sometimes with blood), and show reduced appetite. What makes this different from a simple stomach upset is that the episodes tend to recur, sometimes improving with basic supportive care or a short course of fluids, only to return days or weeks later.

Lethargy and weakness. Dogs with Addison’s disease often seem profoundly tired. They may be reluctant to go on walks, sleep more than usual, and show little interest in activities they once enjoyed. The lethargy can come and go, with the dog appearing almost normal on good days and barely able to get off the bed on bad ones. This waxing and waning pattern is a hallmark of the disease.

Loss of appetite and weight loss. Many Addisonian dogs eat less than usual and gradually lose weight over weeks or months. Some owners describe a dog that picks at food, eats a few bites, and walks away — behavior that is out of character for a dog that was previously enthusiastic about meals.

Increased thirst and urination. While less dramatic than the polydipsia seen in Cushing’s disease, some dogs with Addison’s drink more water than usual and urinate more frequently. This occurs because the kidneys lose their ability to concentrate urine properly without adequate aldosterone.

Muscle tremors and shaking. Some dogs develop noticeable trembling or shaking, particularly during stressful events. This can be subtle — a slight tremor in the hindquarters — or more obvious full-body shaking that owners often attribute to anxiety or cold.

Collapse. In more advanced or acute cases, dogs may collapse suddenly. This can happen during exercise, after a stressful event like a car ride or a visit to the groomer, or seemingly without warning. Collapse is a medical emergency and may indicate an Addisonian crisis.

Addisonian Crisis: A Life-Threatening Emergency

An Addisonian crisis — sometimes called an acute adrenal crisis — is the most dangerous manifestation of the disease and can be fatal without immediate treatment. It occurs when the body’s cortisol and aldosterone levels drop critically low, often triggered by a stressful event that the body cannot mount a proper hormonal response to. Stress in this context includes anything that places demands on the body: illness, surgery, boarding, travel, extreme weather, or even emotional stress like a change in household routine.

During an Addisonian crisis, potassium levels in the blood can rise to dangerous levels, slowing the heart rate (bradycardia) and potentially causing cardiac arrest. Blood pressure drops, blood sugar may fall dangerously low (hypoglycemia), and the dog goes into hypovolemic shock as the circulatory system fails to maintain adequate blood flow to organs.

Signs of an Addisonian crisis include sudden collapse, severe weakness, a slow or irregular heartbeat, pale gums, cold extremities, severe vomiting or diarrhea, and an altered level of consciousness. A dog in crisis needs emergency veterinary care immediately. Treatment involves aggressive intravenous fluid therapy (typically normal saline to dilute the elevated potassium and restore blood volume), intravenous dexamethasone to replace cortisol rapidly, correction of blood sugar if needed, and careful cardiac monitoring. Most dogs respond remarkably well to emergency treatment, often showing dramatic improvement within hours — which is itself a diagnostic clue.

Many dogs are first diagnosed with Addison’s disease in dogs during or immediately after an Addisonian crisis, because the severity of the episode finally prompts the testing that reveals the underlying condition.

Diagnosis: The ACTH Stimulation Test

Diagnosing Addison’s disease requires a specific test because routine blood work alone, while often suggestive, cannot confirm the condition definitively.

Routine blood work clues. A complete blood count and chemistry panel may show several abnormalities that raise suspicion. The classic electrolyte pattern — low sodium and high potassium, with a sodium-to-potassium ratio below 27 — is strongly suggestive of typical Addison’s. Other common findings include elevated kidney values (BUN and creatinine, which can mimic kidney disease), low blood sugar, mild anemia, low albumin, and — unusually — a lack of a stress leukogram. In a sick dog, veterinarians expect to see elevated white blood cell counts reflecting physiological stress. A normal or low white blood cell count in a clearly ill dog is itself a red flag for Addison’s, because the dog lacks the cortisol needed to mount that normal stress response.

The ACTH stimulation test is the gold standard for diagnosing Addison’s disease. The test is straightforward: a baseline blood cortisol level is drawn, the dog receives an injection of synthetic ACTH (cosyntropin), and a second cortisol level is drawn one to two hours later. In a healthy dog, the synthetic ACTH stimulates the adrenal glands to produce a robust increase in cortisol. In a dog with Addison’s disease, both the baseline and post-stimulation cortisol levels are flat — typically less than 2 micrograms per deciliter — because the damaged adrenal glands simply cannot respond to the signal. This blunted response is diagnostic.

Additional testing. Once Addison’s is confirmed, your veterinarian may recommend an electrocardiogram (ECG) to assess for cardiac effects of elevated potassium, abdominal imaging to evaluate the adrenal glands (which are often small or difficult to visualize), and baseline electrolyte panels to guide treatment. An endogenous ACTH level can help distinguish between primary Addison’s (adrenal gland failure, where ACTH is elevated because the pituitary is trying harder to stimulate unresponsive glands) and secondary Addison’s (pituitary failure, where ACTH is low).

Treatment: DOCP Injections and Prednisone

The treatment for Addison’s disease in dogs is conceptually simple: replace the hormones the adrenal glands can no longer produce. In practice, this involves two medications that most Addisonian dogs will take for the rest of their lives.

Desoxycorticosterone pivalate (DOCP). Sold under the brand name Percorten-V or as a generic, DOCP is a long-acting injectable mineralocorticoid that replaces the missing aldosterone. It is typically administered as an injection every 25 to 28 days, though some dogs do well on slightly longer intervals once stabilized. DOCP restores the body’s ability to regulate sodium and potassium properly, which is critical for heart function and fluid balance. The injection is given under the skin (subcutaneously) and can be administered at the veterinary clinic or, with training, by the owner at home.

Prednisone (or prednisolone). A daily oral glucocorticoid replaces the missing cortisol. The dose used for Addison’s disease is a physiologic replacement dose — much lower than the anti-inflammatory doses used for allergies or autoimmune conditions. Most dogs do well on a low daily dose, though the amount may need to be temporarily increased during times of stress such as illness, surgery, travel, or other disruptions to routine. Learning when and how much to increase the prednisone dose is one of the most important aspects of managing an Addisonian dog at home.

Fludrocortisone (Florinef) is an alternative to DOCP that provides both mineralocorticoid and some glucocorticoid activity in a single daily oral tablet. It was the standard treatment before DOCP became widely available and is still used in some cases. However, fludrocortisone requires more frequent electrolyte monitoring, the dose often needs to increase over time, and the glucocorticoid effect may not be sufficient on its own — many dogs on fludrocortisone still need supplemental prednisone.

Dogs with atypical Addison’s disease who have normal electrolytes may initially need only prednisone, without a mineralocorticoid. However, because some of these dogs progress to typical Addison’s over time, regular electrolyte monitoring remains essential even when values have been consistently normal.

Cost of Lifelong Treatment

Because Addison’s disease requires lifelong medication and monitoring, understanding the financial commitment is important for dog owners. Costs vary by location, the size of the dog (larger dogs need higher doses), and whether brand-name or generic medications are used.

DOCP injections are the largest ongoing expense. The medication itself can range from 50 to 150 dollars per injection for a medium-sized dog, administered roughly every four weeks. Generic DOCP has made this more affordable than it once was, but it remains a significant recurring cost. Some owners learn to give the injections at home, which eliminates the office visit fee.

Prednisone is inexpensive — typically just a few dollars per month for the low doses used in Addison’s management. This is one of the least costly aspects of treatment.

Monitoring blood work adds to the annual expense. Electrolyte panels are needed before each DOCP injection during the stabilization period (the first few months), then typically every three to four months once the dog is well-regulated. Each panel may cost 50 to 150 dollars depending on the clinic and region. A comprehensive chemistry panel and complete blood count are usually recommended once or twice a year.

All told, most owners can expect to spend roughly 1,500 to 3,500 dollars per year on Addison’s management for a medium-sized dog, though this can be higher for large or giant breeds and lower for small dogs. Pet insurance, if obtained before diagnosis, may cover a significant portion of these costs. The investment, while real, buys a remarkably normal quality of life for most dogs.

Ongoing Monitoring

Consistent monitoring is the foundation of successful Addison’s management. The goal is to keep electrolyte levels stable and cortisol replacement adequate while minimizing medication side effects.

Electrolyte checks should be performed regularly — typically before each DOCP injection during the first few months, then at intervals your veterinarian recommends once the dog is stable. The sodium-to-potassium ratio is the key value to track. If potassium starts creeping up or sodium drops, the DOCP dose or injection interval may need adjustment.

Watch for signs of under-replacement. A return of lethargy, vomiting, decreased appetite, or weakness near the end of the DOCP injection cycle may indicate that the interval is too long or the dose too low. Keep a simple log of your dog’s energy level, appetite, and any symptoms, noting where they fall in relation to injection dates. This information is invaluable for fine-tuning treatment.

Watch for signs of over-replacement. Too much prednisone can cause increased thirst, increased urination, panting, and weight gain — essentially the symptoms of Cushing’s disease, the opposite condition. If you notice these signs, discuss a dose reduction with your veterinarian rather than adjusting on your own.

Stress dosing. One of the most critical aspects of living with an Addisonian dog is knowing when to increase the prednisone dose. Any significant stressor — a veterinary visit, boarding, travel, illness, extreme heat or cold, a new pet in the house, fireworks, or surgery — may require a temporary increase in prednisone, typically doubling or tripling the usual dose for the duration of the stress and a day or two afterward. Your veterinarian will provide specific guidance on stress dosing protocols for your dog. Always inform any veterinarian treating your dog for any reason that they have Addison’s disease, as this affects anesthesia protocols, fluid choices, and medication decisions.

Dog Breeds at Higher Risk

Addison’s disease can occur in any dog regardless of breed, age, or sex, but certain breeds are statistically overrepresented. Breeds with documented higher risk include:

• Standard Poodles — the breed most commonly associated with Addison’s, with a heritable component well documented in breeding studies
• Portuguese Water Dogs
• Nova Scotia Duck Tolling Retrievers
• Bearded Collies
• Great Danes
• West Highland White Terriers
• Leonbergers
• Wheaten Terriers
• Rottweilers
• Basset Hounds
• Springer Spaniels

The condition is diagnosed more often in young to middle-aged females, though males are certainly affected as well. If you own a breed on this list, mention Addison’s to your veterinarian if your dog develops any of the vague, recurring symptoms described above — early recognition can prevent a crisis. You can explore breed-specific health tendencies in our dog breeds directory.

Prognosis with Treatment

Here is the genuinely encouraging part: the prognosis for Addison’s disease in dogs with appropriate treatment is excellent. Unlike many chronic diseases where treatment slows progression but cannot stop it, hormone replacement for Addison’s disease effectively corrects the underlying deficiency. Dogs on well-managed treatment protocols typically have a normal or near-normal life expectancy.

Most dogs show dramatic improvement within days to weeks of starting treatment. Energy returns, appetite normalizes, vomiting resolves, and the dog that seemed to be fading before your eyes becomes recognizably themselves again. Many owners describe it as getting their dog back.

The key to this positive outcome is consistency. Missed DOCP injections, running out of prednisone, or skipping monitoring blood work can all lead to destabilization and, in the worst case, another Addisonian crisis. But for owners who commit to the routine, Addison’s disease is one of the most successfully managed chronic conditions in veterinary medicine.

Living Well with an Addisonian Dog

Day-to-day life with an Addisonian dog, once treatment is stabilized, is remarkably normal. Most dogs return to their usual activities — playing, walking, swimming, traveling, and doing everything they did before diagnosis. A few practical habits make the journey smoother.

Keep a medication calendar. Mark DOCP injection dates, note when prednisone refills are needed, and set reminders for blood work appointments. Consistency prevents emergencies.

Carry an emergency kit. Keep a small supply of extra prednisone tablets, a written summary of your dog’s diagnosis and medication protocol, and your veterinarian’s emergency contact number in an easily accessible place — especially when traveling. Some owners also carry an injectable dexamethasone kit for true emergencies, with veterinary guidance on when and how to use it.

Communicate with everyone involved in your dog’s care. Pet sitters, dog walkers, boarding facilities, groomers, and any visiting veterinarian need to know your dog has Addison’s disease. A simple card or tag on the collar stating the diagnosis and the need for stress-dose steroids during illness or procedures can prevent dangerous oversights.

Reduce unnecessary stress. While you cannot bubble-wrap your dog’s life, you can minimize predictable stressors. If your dog finds the groomer stressful, stress-dose prednisone beforehand. If thunderstorms are a trigger, plan ahead. Routine and predictability are an Addisonian dog’s best friends.

Connect with other Addisonian dog owners. Online communities of owners managing this condition are active and supportive. The shared experience of tracking injection schedules, recognizing subtle symptom changes, and navigating the occasional setback is genuinely helpful, both practically and emotionally.

If you are thinking about adopting a dog with Addison’s disease, know that these dogs are often overlooked in shelters and rescues precisely because the diagnosis sounds intimidating. In reality, a stabilized Addisonian dog requires a monthly injection, a daily low-dose pill, and periodic blood work — a manageable commitment that rewards you with a dog who is, in every meaningful way, healthy and full of life.

Frequently Asked Questions

Is Addison’s disease in dogs curable?

Addison’s disease caused by immune-mediated destruction of the adrenal glands is not curable — the damage to the glands is permanent. However, it is one of the most effectively managed chronic conditions in veterinary medicine. With lifelong hormone replacement therapy, most dogs live normal, active lives with an excellent quality of life. Iatrogenic Addison’s disease, caused by medication or abrupt steroid withdrawal, may resolve once the underlying cause is addressed.

How long can a dog live with Addison’s disease?

With proper treatment and monitoring, dogs with Addison’s disease can live a normal lifespan. The condition itself does not shorten life expectancy when well-managed. Many Addisonian dogs live for years after diagnosis with no reduction in quality of life. The critical factor is consistent medication and regular veterinary monitoring to keep hormone levels where they need to be.

What triggers an Addisonian crisis?

An Addisonian crisis is typically triggered by a stressful event that overwhelms the body’s limited hormonal reserves. Common triggers include illness or infection, surgery, vigorous exercise, boarding or travel, extreme temperatures, emotional stress, and missed medication doses. The body needs more cortisol during stress, and an Addisonian dog cannot produce it. Stress-dosing prednisone before known stressful events is the primary strategy for prevention.

Can I give my Addisonian dog the DOCP injection at home?

Yes, many veterinarians will train owners to administer DOCP injections at home. The injection is given subcutaneously, similar to how insulin is given to diabetic dogs. Home administration can reduce costs by eliminating the office visit fee and is more convenient for both dog and owner. You will still need to visit the clinic regularly for blood work to check electrolyte levels and ensure the dose remains appropriate.

How do I know if my dog’s Addison’s disease is well-controlled?

A well-controlled Addisonian dog looks and acts like a healthy dog — good energy, normal appetite, stable weight, no vomiting or diarrhea, and consistent behavior throughout the DOCP injection cycle. Electrolyte levels on blood work should be within normal ranges. If your dog seems to slump or show symptoms toward the end of the injection cycle, the interval may need to be shortened or the dose increased. Regular communication with your veterinarian and keeping a symptom log are the best tools for maintaining good control.

Should I adopt a dog with Addison’s disease?

Absolutely, if you are prepared for the commitment. Addisonian dogs are often passed over in shelters because the condition sounds complicated, but the daily reality is a single low-dose pill each morning and a simple injection once a month. These dogs deserve loving homes just as much as any other, and many adopters find that caring for an Addisonian dog is far less demanding than they expected. Visit our adoption page to find dogs looking for their forever homes.