What is Hypoadrenocorticism (Addison’s Disease) in Dogs?

Introduction

When Tom’s usually energetic and playful Rottweiler, Duke, began displaying signs of lethargy, loss of appetite, and occasional vomiting, he knew something wasn’t right. Concerned about Duke’s well-being, Tom scheduled an appointment with their trusted veterinarian. After conducting a thorough examination and running several tests, the vet informed Tom that Duke was suffering from Addison’s Disease, a diagnosis Tom had never heard of before.

Addison’s disease (also known as hypoadrenocorticism) is a condition that causes young to middle-aged female dogs to lose weight and become lethargic. Addison’s disease occurs when the body produces less cortisol than usual. Low cortisol levels cause it, a hormone the adrenal glands produceFirst, a.

The adrenal glands are small glands situated just above each kidney. They secrete two significant hormones, cortisol and aldosterone, that regulate many bodily processes. For example, cortisol helps the body cope with stress, while aldosterone controls blood pressure, salt retention, and water balance. In addition, these hormones help maintain normal blood sugar levels and keep the immune system working correctly.

Symptoms usually appear after two years, although younger dogs can also develop the uncommon disease. Three types of Addison’s Disease include primary, secondary, and Congenital. Primary Addison’s disease affects the adrenal gland itself, while secondary Addison’s disease involves other organs that affect the production of cortisol. Congenital Addison’s disease is present at birth and does not progress over time.

Causes of Hypoadrenocorticism in Dogs

Dogs can develop Addison’s disease just like humans do. However, low levels of cortisol in the body cause it. Baseline cortisol is produced naturally by the adrenal glands and helps regulate blood pressure, metabolism, and immune system function. When cortisol levels drop, symptoms appear. These include fatigue, weight loss, vomiting, diarrhea, and decreased appetite.

There are several possible reasons for low cortisol levels in dogs. One reason could be stress. Stressful situations like moving, boarding, or traveling can trigger the release of adrenaline into the bloodstream. Adrenaline increases heart rate, breathing, and blood flow to muscles. This can lead to increased production of cortisol. Another possibility is thyroid problems. Thyroid hormones play a role in regulating cortisol levels. Therefore, low levels of thyroid hormone can result in low cortisol levels. Finally, certain oral medications can decrease cortisol levels. Examples include steroids, antihistamines, and antidepressants.

Symptoms of Canine Hypoadrenocorticism

Clinical signs of Addison’s disease in dogs include vomiting, diarrhea, weight loss, loss of appetite, weakness, lethargy, irregular heart rate, excessive thirst, increased urination, fever, muscle tremors, seizures, blindness, and death.

The most common symptom of canine Addison’s Disease is vomiting. Vomiting occurs when there is too much fluid in the stomach. This excess fluid comes from the intestines. When the dog vomits, he loses water through his mouth. If the dog continues to vomit, he will lose even more fluids.

• Diarrhea

Diarrhea is caused by inflammation of the small intestine. It results in frequent bowel movements. In some cases, the feces contain blood.

• Weight Loss

Dogs usually become weak because they need more energy to move around. They also get tired quickly. A dog who is losing weight should see a veterinarian immediately.

• Weakness

Weak dogs cannot stand up without help. They are unable to walk correctly. Their muscles feel stiff.

• Lethargy

Lethargic dogs are affected by slow responses to commands. They seem sleepy. They sleep longer than usual.

• Depression

This is yet another symptom of canine Addison’s disease. Depressed dogs are sad. They cry often. They may refuse to eat.

In addition, some dogs develop secondary infections because their immune systems are compromised. The most common secondary infections caused by Addison’s disease in dogs include pneumonia, urinary tract infections, skin infections, ear infections, eye infections, diarrhea, etc. If left untreated, these infections can lead to death.

Diagnosis of Hypoadrenocorticism in Dogs

To accurately diagnose Addison’s disease, veterinarians perform tests to measure levels of hormones in the patient’s blood. First, a physical examination is needed to see any lumps and problems a dog may have. They may also look for elevated ACTH (Adrenocorticotropic hormone) or cortisol. An increased level of ACTH indicates that the pituitary gland is producing excessive amounts of the hormone. This could reveal the presence of a tumor or infection. An elevated amount of cortisol suggests that the adrenals aren’t making enough of the hormone. Other tests may be performed to rule out other diseases affecting cortisol levels.

Addison’s disease in some dogs is diagnosed after they exhibit Addisonian crisis. Your veterinarian will diagnose the condition based on history, physical exam, and lab findings. There are no specific tests for diagnosing Addison’s in dogs. Instead, your vet will use a combination of definitive dog diagnoses, including:

• History – What does the dog eat? How often does he exercise? Is there anything else about his health that seems off?
• Physical Examination – Does he seem thin? Are his muscles weak? Do you notice any changes in his behavior?
• Lab Tests – They will perform a blood test to get a complete blood count, blood samples, urinalysis, fecal analysis, etc.

Treatments of Addison’s Disease in Dogs

Proper treatment depends on the severity of the problem and how long it has been going on. Primarily, affected male dogs respond quickly to treatment. In mild cases, your veterinarian might recommend giving your dog extra fluids through IV fluids, daily pills, or oral supplements. In addition, your vet may prescribe medications to help control seizures, reduce inflammation, increase appetite, and prevent infection. If you notice any changes in behavior, call your doctor immediately.

There are several types of treatments for Addison’s disease. Your veterinarian will determine which is best for your dog based on its symptoms and overall health.

1. The most common treatment is the daily administration of steroids, such as prednisone. This helps control the inflammation in the adrenals and reduces the risk of infection and fluid accumulation in the lungs.
2. Another type of treatment involves giving your dog a drug called Mitotane. This drug suppresses the production of hormones in the body, including cortisol, which stimulates the immune system.
3. A third type of treatment uses a drug called Trilostane. This drug blocks the enzyme that converts cholesterol into pregnenolone, which is needed to make corticosteroids like cortisol. As a result, less cortisol is produced.

Prevention of Canine Addison’s Disease

Prevention includes regular veterinary checkups, good nutrition, good quality of life, exercise, and stress management. Routine physical exams are recommended, including checking the heart rate and temperature. In addition, a veterinarian should examine your dog at least once every six months. Your vet will look for signs of illness and perform tests to determine if your dog has any underlying medical conditions.

Addison’s disease is not typically preventable, but there are exceptions. A medication-induced Addison crisis is one such case where it is possible to take action to avoid a life-threatening situation.

If your dog is on the medications mitotane or Trilostane, ensure you know the signs of Addison’s disease. An accidental overdose could lead to an Addisonian crisis. Your veterinarian can help guide you through monitoring your dog’s medications.

Keep these medications away from your dog at all times. Make sure you’re familiar with how to administer your dog’s pills. And keep an eye on your dog while he takes his meds.

Frequently Asked Questions