In both diseases, dogs tend to drink and urinate excessively, and special diabetes food can support your dog in both cases. However, the two conditions differ in their cause, treatment, and partly in their symptoms.

Cushing

Cushing’s syndrome is caused by an excess of cortisol, a hormone produced by the adrenal glands. Overproduction can be due to a tumor in the adrenal glands or the pituitary gland or as a result of long-term corticosteroid treatment.

Symptoms of Cushing:

• Increased thirst and frequent urination
• Increased appetite
• Muscle breakdown and weakness
• Swollen abdomen, weight gain
• Fatigue and lethargy
• Hair loss, bald spots, and skin problems
• Neurological symptoms such as seizures and vision loss

Treatment for Cushing usually involves medication to reduce cortisol production. In some cases, surgery may be necessary.

Diabetes

Diabetes mellitus, also known as sugar diabetes, is a disruption in insulin production. Insulin is needed to maintain stable blood sugar levels. A lack of insulin means that sugar from food is not properly absorbed into the cells. This leaves glucose in the bloodstream, causing various health issues. Diabetes can be linked to obesity, diet, and age, but it may also result from other (hormonal) disorders or develop during pregnancy.

There are four types of diabetes in dogs:

Diabetes Type 1 (insulin-dependent):
The most common form, with about half of diabetic dogs having Type 1. It mainly occurs in dogs over the age of three. In this type, the pancreas produces insufficient insulin, leading to high blood sugar levels. Treatment for Type 1 usually requires daily insulin injections.

Diabetes Type 2:
This type is rare in dogs but more common in cats. The body produces enough insulin, but the cells do not respond properly to it. This also results in high blood sugar levels.

Diabetes Type 3 (secondary diabetes):
This type develops due to other health issues, such as pancreatitis, long-term use of corticosteroids, or high cortisol levels in the blood caused by Cushing’s. Hormones like cortisol can make the dog’s body less responsive to the insulin it produces. As a result, the pancreas must work harder, leading to insulin deficiency. Treating Type 3 diabetes also requires addressing the underlying cause.

Diabetes Type 4 (gestational diabetes):
This type only occurs in pregnant females. The fertility hormone progesterone triggers this form of diabetes. Spayed females are not affected, but it can occur in intact females during their heat cycle. Gestational diabetes can be fatal for both the mother and her puppies. However, it often resolves quickly if the pregnancy is terminated or after the puppies are born. Older females are more commonly affected.

Symptoms of diabetes in dogs:

• Increased thirst and frequent urination
• Increased appetite while losing weight
• Fatigue
• Strange body odor
• Cloudy eyes

Treatment for diabetes typically involves daily insulin injections, a diet low in sugars and carbohydrates, and regular monitoring of blood sugar levels.

Cushing and Diabetes Together?

Dogs can have both Cushing’s syndrome and diabetes simultaneously. Small-scale studies have shown that diabetes is often diagnosed first. The diagnosis of Cushing usually follows later when the dog does not respond well to insulin injections. However, this does not mean that diabetes causes Cushing – it is often the other way around.

High cortisol levels associated with Cushing disrupt blood sugar regulation. A (prolonged) excess of cortisol harms health and interferes with many bodily processes. Dogs with Cushing tend to have higher blood sugar levels, which can eventually lead to diabetes. For this reason, it is advisable to regularly monitor the blood sugar levels of a dog with Cushing and to avoid feeding it sugary foods or allowing it to become overweight.

Cortisol works in many ways opposite to insulin. When there is too much cortisol in the blood, insulin resistance can develop, where the body becomes less responsive to insulin. In such cases, more and more insulin is needed to regulate blood sugar levels. This can overwork the pancreas, ultimately leading to Type 3 diabetes.