Symptoms of Cat Diabetes

As a veterinary assistant here in Frisco, Texas, I have seen something really important: diabetes in cats often starts quietly. Many pet parents feel guilty for missing the early signs, but the truth is these symptoms can look like normal aging or “my cat is just being picky.”

This guide is here to help you spot the most common, practical signs that your cat may be struggling with diabetes, and what to do next. Early action can make a huge difference in comfort, health, and longevity. Even though I am writing from Frisco, the signs and next steps apply anywhere.

What cat diabetes is

Feline diabetes mellitus is most often similar to type 2 diabetes in people. Your cat’s body is not using insulin well (insulin resistance), and over time they may not produce enough insulin either. Insulin helps move glucose (sugar) from the bloodstream into the body’s cells for energy.

When insulin is not doing its job, glucose builds up in the blood. The body tries to get rid of the extra sugar through urine, which is why many of the classic symptoms involve drinking and peeing more.

Early symptoms you can catch at home

These are the most common signs pet owners notice first. If you see more than one of these together, it is worth calling your veterinarian soon.

Drinking more water (polydipsia)

If you find yourself refilling the water bowl more often, or your cat starts seeking water in unusual places (the tub, sink, cups), take note.

Urinating more (polyuria)

With excess glucose spilling into urine, the body pulls extra water along with it. You may notice:

• Larger urine clumps in the litter box
• More frequent litter box use
• Accidents outside the box, especially if the box is far away or hard to access

Increased appetite (polyphagia) but weight loss

This combo is a big red flag. Even if your cat is eating well, their cells are “starving” because glucose cannot get in efficiently. The body starts breaking down fat and muscle for fuel.

Symptoms that look like other problems

Here is the tricky part: some diabetes signs overlap with thyroid disease, kidney disease, urinary tract issues, stress, or dental pain. That is why testing matters.

Low energy or sleeping more

Because their cells are not getting fuel properly, many diabetic cats seem tired or less playful.

Changes in coat and skin

You might notice a dull coat, dandruff, or reduced grooming. Sometimes this is from dehydration, sometimes from feeling unwell overall.

More infections than usual

High blood sugar can make it easier for bacteria and yeast to thrive. Watch for:

• Urinary tract infections (straining, frequent trips, blood in urine)
• Skin infections
• Ear infections

Hind leg weakness or a “flat-footed” stance

Some diabetic cats develop diabetic neuropathy, which can look like weakness in the back legs or walking lower to the ground than usual (sometimes called a plantigrade stance). This is a very memorable sign for many families, and it is worth mentioning to your vet right away.

Urgent symptoms: get help now

Some diabetic cats can develop a dangerous emergency called diabetic ketoacidosis (DKA). This happens when the body is breaking down fat rapidly and producing ketones, making the blood more acidic.

Go to an emergency vet immediately if you notice:

• Not eating, especially if it is paired with vomiting, weakness, or sleepiness
• Vomiting, especially repeated vomiting
• Severe lethargy or weakness
• Fast or labored breathing
• Dehydration (tacky gums, sunken eyes)
• A fruity or acetone-like smell on the breath (this can happen with DKA, but it may not be present)

If your cat is already on insulin, treat “not eating,” sudden weakness, wobbliness, or unusual sleepiness as urgent. Those can be signs of hypoglycemia (low blood sugar), which is also an emergency.

Trust your instincts. If your cat looks “off” in a way you cannot explain, it is always okay to call your vet or an emergency hospital and ask what they recommend.

How vets diagnose cat diabetes

Diagnosis typically involves a combination of your cat’s symptoms plus lab testing.

• Blood glucose: often elevated in diabetic cats
• Urinalysis: glucose in urine is a classic finding; may also show ketones
• Fructosamine: helps confirm if blood sugar has been high over time (useful because some cats get “stress hyperglycemia” at the clinic)
• Additional labs: kidney values, liver enzymes, cholesterol, and screening for infection can guide treatment

What to do if you suspect diabetes

Here are steps that help your veterinarian and protect your cat while you wait for an appointment.

1) Track what you are seeing

• How often you refill the water bowl
• How many litter clumps per day, and if they are larger
• Current weight (even a rough estimate helps)
• Appetite changes and any vomiting
• Any hind leg weakness or changes in how they walk

2) Do not restrict water

If your cat is drinking more, it is often because they are trying to stay hydrated. Always provide fresh water.

3) Book a vet visit soon

If your cat is bright and eating, make an appointment within the next few days. If your cat is not eating, vomiting, acting weak, breathing fast, or seems dehydrated, treat it like urgent care.

4) Avoid sudden diet changes without guidance

Nutrition is a key part of diabetes management, but switching foods abruptly can cause stomach upset and can complicate early treatment decisions. If you want to move toward a lower carbohydrate, higher protein wet food plan, do it with your veterinarian’s help.

5) Bring the details your vet will ask for

• Food brand, flavor, and how much you feed per day (plus treats)
• Any recent weight change and your best estimate of current weight
• Photos of the litter box clumps or a quick note on their size and frequency
• A short video if you catch increased drinking or unusual walking
• Any medications, especially steroids (prednisolone, dexamethasone) or progestins

What treatment can look like

Many cats do very well once stabilized. Common treatment pieces include:

• Insulin: usually given at home with tiny injections. Most cats tolerate it better than you would think.
• Diet: often a veterinarian-recommended canned diet that is higher in protein and lower in carbohydrates.
• Weight management: safe, gradual weight loss for overweight cats improves insulin sensitivity.
• Monitoring: at-home observation plus periodic glucose curves or continuous glucose monitoring, depending on your clinic.

In the beginning, it is normal for your vet to adjust the insulin dose and recheck labs more frequently. The goal is a dose that keeps your cat comfortable and safe, without pushing blood sugar too low.

One of the most encouraging facts: some cats can go into diabetic remission, especially when the condition is caught early and treated consistently.

Important safety note: hypoglycemia

Once a cat starts insulin, the biggest immediate risk is hypoglycemia (low blood sugar). Call an emergency clinic right away if you see sudden weakness, wobbliness, collapse, tremors, or seizures.

Risk factors you can influence

Not every case is preventable, but there are meaningful steps that lower risk.

• Excess weight: overweight and obese cats are at higher risk
• Low activity: indoor cats benefit from daily play
• Calories over time: the biggest diet-related risk is long-term overeating and weight gain; food type and carbohydrate level can matter for some cats, but maintaining a healthy body condition is the most important goal
• Age: diabetes is more common in middle-aged to older cats
• Steroid medications: long-term steroids can increase risk in some cats

Other risk factors (not your fault, just helpful to know) can include being male and neutered, and in some regions certain breeds such as Burmese.

If you want one simple starting point, aim for a healthy body condition. Even small changes like two short play sessions a day and measured meals can add up.