What Is Diabetes in Cats? What Are the Signs?

Diabetes mellitus in cats is a chronic condition where the body either doesn’t produce enough insulin or can’t effectively use it.  

Insulin is essential for regulating blood sugar (glucose) levels, and when it’s insufficient or ineffective, glucose builds up in the bloodstream, leading to high blood sugar levels. 

Diabetes is a relatively common condition in cats, with estimates suggesting that between 1 in 100 and 1 in 500 cats will develop diabetes in their lifetime.  

Types of Diabetes in Cats  

As with humans, cats can develop different forms of diabetes, including:  

• Type I Diabetes (insulin-dependent diabetes mellitus): This form of diabetes is rare in cats. It develops when a cat’s pancreas produces little to no insulin, making it impossible to regulate blood sugar levels. As a result, lifelong insulin therapy is required.  
• Type II Diabetes (non-insulin-dependent diabetes mellitus): This is—by far— the most common type of diabetes in cats. It occurs when the body produces normal or even elevated levels of insulin, but due to insulin resistance, it can’t effectively regulate blood sugar, says Mandi Shearhart, DVM, staff veterinarian at Best Friends Animal Society in Fayetteville, Arkansas. 

Recognizing the symptoms of diabetes in cats early is key to preventing complications.  

Take your cat to the vet immediately if they’re experiencing any of the following symptoms:  

• Increased thirst  
• Increased urination 
• Unexplained weight loss (despite a normal or increased appetite) 
• Lethargy 
• Dull or unkempt coat 
• Urinating outside the litter box (due to urinary tract infections) 
• Increased appetite (initially), then decreased appetite 
• Irritability or aggressiveness 
• Vomiting 
• Frequent urinary tract infections 
• Muscle wasting  
• Weakness in the back legs (due to diabetic neuropathy) 

“Diabetes mellitus is caused by either the body not secreting enough insulin to control blood sugar or the body developing a resistance to the insulin secreted so that it does not respond to it well enough to control blood sugar—or sometimes both,” Dr. Shearhart explains. 

But what causes this dysfunction? Several risk factors increase insulin resistance, and thus, the likelihood of diabetes in cats, including:

• Obesity: Dr. Shearhart says obesity in cats is the biggest risk factor for developing diabetes.  
• Lack of physical activity: This can contribute to obesity and insulin resistance.  
• Increasing age: Middle-aged and senior cats, particularly those 10–13 years old, are more susceptible. 
• Sex: Diabetes is more common in male cats than female cats. 
• Steroid use: Studies suggest the use of corticosteroids can induce diabetes.  
• Genetics: Some breeds of cats have a higher incidence of diabetes, including Burmese, Tonkinese, and Norwegian Forest Cats. 
• Certain diseases: “When type I diabetes is seen in cats, it’s usually secondary to chronic pancreatitis that has damaged insulin-producing cells,” says Dr. Shearhart, who adds that Cushing’s disease and chronic kidney disease can also play a role.  

If you notice signs of diabetes in your cat, it’s important to schedule a veterinary visit as soon as possible.  

Diabetes in cats is diagnosed based on a combination of symptoms observed by pet parents and elevated glucose levels in the blood and urine, confirmed through blood tests and urinalysis. 

When it comes to treatment for diabetes in cats, Dr. Shearhart says many diabetic cats need daily, at-home injectable insulin, such as ProZinc or Vetsulin, to keep their blood sugar levels in check.  

New treatments, such as Senvelgo (an oral medication) are also available as an alternative to insulin for some cats, says Dean Vicksman, DVM, president of EveryCat Health Foundation in Wyckoff, New Jersey. 

With the right care, your diabetic cat can still live a happy and comfortable life. Here’s how you can support them at home: 

• Stick to a strict insulin and feeding schedule. “Giving insulin (or oral medication like Senvelgo) at the same time every day, along with a stable feeding schedule, helps keep blood sugar in check,” Dr. Vicksman says.  
• Ask your vet about a prescription diabetic diet. Options like Hill’s Prescription Diet m/d GlucoSupport dry food or Royal Canin Glycobalance wet food are formulated to help regulate blood sugar.  
• Help them maintain a healthy weight. If your cat is overweight, gradual weight loss through portion control and light activity can improve insulin sensitivity. Encourage movement with wand toys, like the Frisco Bird With Feathers Teaser Wand, or interactive toys, such as the Catstages Tower of Tracks.  
• Provide easy access to fresh water. Diabetic cats are more prone to dehydration, so place multiple water bowls around the house or invest in a cat water fountain, like the PetNF Transparent Fountain, to encourage more drinking.  
• Make litter boxes accessible. Frequent urination is a common symptom in diabetic cats, so it’s important to place litter boxes in easily accessible locations. If your cat has diabetic neuropathy and struggles with mobility, Dr. Vicksman says a low-entry litter box, like the KittyGoHere Senior Cat Litter Box, can make bathroom trips more manageable.  
• Provide comfy bedding. For cats with diabetic neuropathy, Dr. Vicksman recommends providing plenty of soft, supportive bedding, like the FurHaven Faux Fur & Suede Bed, to help them rest more comfortably. 
• Monitor blood glucose at home. A pet glucose meter kit, like the AlphaTRAK 3 Blood Glucose Monitoring Kit, allows for at-home blood sugar monitoring. Keeping a log of glucose readings, insulin doses, and symptoms can help fine-tune treatment. 
• Schedule follow-ups. “Sticking with vet follow-ups is crucial,” says Dr. Vicksman. “Skipping rechecks or trying to manage diabetes without proper monitoring often leads to mismanagement and more health problems down the line.”  

While some risk factors for diabetes—such as age and genetics—are beyond your control, there are several steps you can take to reduce your cat’s chances of developing the condition.  

• Keep your cat at a healthy weight. If your cat is overweight, help them gradually lose weight through portion control and light physical activity.  
• Feed a high-protein, low-carb diet. “Many dry foods are loaded with carbohydrates, which can contribute to insulin resistance over time, so feeding a high-protein, low-carb diet—especially wet food—can help lower the risk,” Dr. Vicksman says. Try the Weruva Cats in the Kitchen Cuties Variety Pack.  
• Encourage daily exercise. Physical activity helps maintain a healthy weight and supports overall health. A cat tree, like this 61-inch Frisco Faux Fur Cat Tree, or climbing shelves, like TRIXIE Lounger Cat Shelves, can also encourage natural movement and play. 
• Schedule regular veterinary checkups. Catching diabetes early may allow for better management or even the chance to reverse it with diet and weight control alone, Dr. Vicksman says.