Dogs and cats get diabetes too. Here’s what to look out for and how to manage it

Learning a pet has diabetes can be a shock. Sadly, about 20% of diabetic cats and dogs are euthanised within a year of diagnosis due to the impacts on the pets’ health and their owners’ lifestyle and finances.

However, the disease can be managed. And for cats, but not dogs, effective early treatment even gives them a good chance of remission.

Diabetes in cats and dogs is fairly common – though not as common as in humans. It affects about 1.5% of dogs and 0.5–1% of cats.

So what exactly is diabetes? What are the warning signs? And how do you manage the disease?

Being overweight increases the risk of diabetes in cats, as in people, and to a lesser extent in dogs. Mary Swift/Shutterstock

What is diabetes?

Glucose is the body’s primary energy source. Insulin, a hormone produced in the pancreas, regulates levels of this blood-borne sugar, its uptake into cells and its storage in the liver and muscles.

In animals with diabetes, the body does not secrete enough insulin. The result is high glucose levels (hyperglycemia) and associated clinical signs.

Some breeds and unspayed female dogs are more at risk, as are middle-aged, older and obese animals.

Diabetes mellitis (its full scientific name) is generally classified into four main types:

1. Type 1 diabetes

This form results from autoimmune destruction of insulin-producing pancreatic cells, because the immune system attacks them by mistake.

Type 1 is common in dogs but rare in cats. Its onset in dogs, usually in middle age, is often insidious.

Type 1 diabetes is most common in dogs. Parilov/Shutterstock

2. Type 2 diabetes

This form is characterised by insulin resistance and dysfunction in cells that produce insulin. It accounts for most cases in cats but is rare in dogs.

The major risk factors are obesity and increasing age. Other factors include genetics, physical inactivity and being kept indoors and the use of glucocorticoid steroids.

In the earlier stages, when the cat is still producing some insulin of its own, type 2 diabetes can be managed using drugs that reduce blood glucose. The drugs are formally known as “sodium-glucose transporter 2” or (SGLT2) inhibitors.

For more advanced cases, insulin injections are essential. Long-acting insulin in cats typically controls blood glucose levels better than the intermediate-acting insulins typically used in dogs.

Weight loss is also important for overweight or obese animals. The maximum safe rate of weight loss is 1-2% of body weight a week in cats, so achieving an ideal weight can take 6–12 months. Adding steamed zucchini to each meal can help with weight loss.

Getting the diet right is important for managing diabetes in cats and dogs. Moshe EINHORN/Shutterstock

3. Other specific types

Some diabetes types are caused by other medical conditions such as chronic pancreatitis, which is common in diabetic dogs, or acromegaly in cats, where too much growth hormone results in marked insulin resistance.

4. Dioestrus and Gestational diabetes

Diabetes can occur in older female dogs after they have been in heat. In dioestrus, secretion of increased growth hormone from mammary glands counteracts insulin. Although very rare in pets, female dogs can get transient diabetes in pregnancy.

What are the signs to look for?

Signs of diabetes usually emerge slowly over weeks to months. If diagnosis is delayed, the pet’s health can decline rapidly over 24–48 hours, leading to death if not immediately treated.

Signs to look out for include increased thirst and urination, increased appetite and weight loss. However, some dogs and up to 50% of cats with diabetes have a reduced appetite.

Diabetic cats’ posture may change to a flat-footed stance and they may lose jumping ability. Diabetic dogs are prone to cataracts.

Diagnosis involves documenting persistently high blood glucose levels along with glucose in the urine. Certain or tests tests can confirm the diagnosis by measuring average blood glucose over the past several weeks.

In cats, early diagnosis before clinical signs appear can be difficult because the stress of visiting the vet often raises blood glucose levels. Multiple measurements and/or urine analysis, preferably at home, may be needed to confirm the diagnosis.

What are the treatment options?

Tailored monitoring and treatment can improve quality of life and reduce euthanasia rates. In cats, early intervention can potentially delay onset of clinical diabetes and reduce the burden of long-term insulin treatment.

Insulin therapy remains the cornerstone of treatment. Options range from short-acting for immediate control to intermediate and long-acting insulin for daily management.

In dogs, types of insulin known as “porcine lente” or “protamine zinc” are commonly used. Consistent feeding schedules and exercise help stabilise blood glucose.

SGLT2 inhibitors have almost no risk of clinical signs from low blood glucose (hypoglycemia) and can be given with food. This may help overcome common treatment barriers such as having to give twice daily injections for cats with diabetes.

However, these treatments are most effective with early diagnosis, as they require the cat to still produce enough insulin to suppress formation of ketones (acids your body makes when it breaks down fat for energy). Especially in the first few weeks of treatment, ketone monitoring is crucial to avoid life-threatening complications.

For cats showing more advanced signs of diabetes, their own insulin secretion is unlikely to be enough for management with oral SGLT2 inhibitors, and insulin injections are needed. Longer-acting insulin is more effective for inducing remission.

Dietary changes are essential. Low-carbohydrate diets improve remission rates for cats when combined with long-acting insulin. However, such diets might not be suitable when using SGLT2 inhibitors.

In newly diagnosed cats without other medical conditions, tight control of blood glucose levels can lead to remission in up to 80% of cases. Sustained weight management is then key to maintaining it without other treatment.

Dogs rarely achieve remission because the destruction of insulin-producing cells in type 1 diabetes is irreversible.

Diabetic cats and dogs can have a good life

Diabetes in dogs and cats is manageable with the right vet care, owner commitment, and adjustments to diet and body weight.

Advances in home glucose monitoring, including continuous monitors, mean vets and pet owners can better track and manage blood glucose.

For most diabetic dogs it’s a lifelong condition. For cats, the prospect of remission, as well as giving owners hope, underscores the need for awareness of early symptoms and early vet care.

Through diligent weight management, diet, glucose monitoring and insulin dose adjustments, pets with diabetes can live healthy, fulfilling lives.