Understanding Diabetes in Your Cat

What is feline diabetes?

Diabetes mellitus means your cat’s body is having trouble controlling blood sugar.

Normally, food is broken down into glucose, which is a type of sugar used for energy. A hormone called insulin helps move that sugar from the bloodstream into the body’s cells. In diabetic cats, the body either does not make enough insulin, or the body does not respond to insulin properly. The result is that sugar builds up in the blood, while the body’s cells are left short on usable energy.

In cats, diabetes often behaves a bit like type 2 diabetes in people. It is commonly linked with insulin resistance, which means the body is not listening to insulin properly. This can happen with obesity, age, low activity levels, other illnesses, or some medications such as steroids.

The good news is that many diabetic cats can still have a very good quality of life. Some cats can even go into diabetic remission, meaning they may no longer need diabetes medication for a period of time.

What signs might you notice at home?

Early signs can be subtle, especially in cats, because they are tiny secret agents when it comes to hiding illness. Things to watch for include:

Common signs of diabetes

• Drinking more water than usual
• Urinating more often, larger clumps in the litter tray, or accidents outside the tray
• Increased hunger
• Weight loss, even if your cat is eating well
• Tiredness or sleeping more
• Poor coat condition or looking less well-groomed
• Weakness in the back legs
• Walking flatter on the back feet, sometimes called a “plantigrade stance”

Some cats seem fairly normal at first, so weight changes, thirst changes, and litter tray changes are often the earliest clues.

How is diabetes diagnosed?

A single high blood sugar reading does not always mean diabetes, because cats can get stress hyperglycaemia at the vet clinic. That means their blood sugar can rise just from being worried, travelling, or being handled.

To diagnose diabetes properly, your vet may recommend:

• Blood glucose testing
• Urine testing to check for glucose and ketones
• Fructosamine testing, which gives an idea of average blood sugar over the previous 1 to 2 weeks
• A full blood and urine profile to look for other health issues
• Sometimes a continuous glucose monitor, often called a CGM, which tracks glucose levels at home over several days

Your vet is not just looking for “high sugar.” They are checking whether the high sugar is persistent, whether it is affecting your cat, and whether there are any complications or other illnesses involved.

What does this mean for your cat?

A diabetes diagnosis does mean your cat will need extra care, monitoring, and routine. But it does not mean your cat cannot live happily.

The main goals are:

1. Reduce the signs of diabetes, such as excess thirst, urination, hunger, and weight loss.
2. Keep your cat feeling well and comfortable.
3. Avoid blood sugar going too low.
4. Look for and treat any other problems that may make diabetes harder to control.
5. Give your cat the best chance of remission where possible.

Think of diabetes management as steering a small boat, not flipping a light switch. We make careful adjustments, watch how your cat responds, and keep improving the plan.

What treatment might involve

Treatment depends on your cat’s health, blood results, appetite, hydration, and whether there are ketones or other complications.

1. Insulin injections

Insulin is a common and effective treatment for diabetic cats. Many cats start on insulin given once or twice daily, depending on the type used and the vet’s plan.

Most owners are understandably nervous at first, but the needles are very small, and most cats tolerate injections surprisingly well. Many barely notice once everyone has had a little practice.

2. Oral diabetes medication

Some newly diagnosed diabetic cats may be suitable for a newer oral medication called an SGLT2 inhibitor. These medications are not insulin. They help lower blood sugar by encouraging the body to pass extra glucose through the urine.

They are not suitable for every cat. Cats who are unwell, vomiting, not eating, dehydrated, or have ketones may need insulin instead. Cats on these medications need careful monitoring, especially in the first couple of weeks.

3. Diet and weight management

Diet is an important part of care. Many diabetic cats benefit from a diet that is:

• Higher in protein
• Lower in carbohydrate
• Often wet food based, if suitable for the individual cat
• Carefully portioned to support a healthy body weight

For overweight cats, gradual weight loss can improve insulin resistance. This must be done safely, because cats should never be crash-dieted.

4. Monitoring

Monitoring may include:

• Watching thirst, urination, appetite, energy, and weight
• Recheck visits at the clinic
• Blood or urine glucose checks
• Ketone checks in some cats
• A continuous glucose monitor in some cases
• Periodic blood and urine tests

Your observations at home are hugely important. The day-to-day clues often tell us as much as the numbers do.

What to expect in the first few weeks

The first few weeks are usually the busiest part.

You may need:

• More frequent rechecks
• Dose adjustments
• Home notes about appetite, drinking, urination, and behaviour
• Monitoring for low blood sugar if your cat is on insulin
• Monitoring for ketones, especially if your cat is on an oral SGLT2 medication
• Patience while the right treatment balance is found

It is normal for diabetic control to take weeks to months, not days. The first plan is often the starting map, not the final destination.

Important warning signs

Please contact the clinic urgently if your cat:

• Stops eating or eats much less than normal
• Vomits repeatedly
• Seems weak, wobbly, collapsed, or unusually sleepy
• Has tremors or seizures
• Seems very dehydrated
• Is breathing abnormally
• Has sudden worsening thirst, urination, or weight loss
• Seems generally “not right”

For cats on insulin, signs such as wobbliness, weakness, strange behaviour, tremors, or seizures may suggest low blood sugar, which can be an emergency.

For cats on oral SGLT2 medication, poor appetite, vomiting, lethargy, or seeming unwell can be concerning because some cats can develop a serious complication called diabetic ketoacidosis, even when blood sugar is not extremely high.

Can cats recover from diabetes?

Some cats can go into remission. This means their blood sugar stays controlled without insulin or oral diabetes medication for at least several weeks.

Remission is more likely when:

• Diabetes is diagnosed and treated early
• Blood sugar is controlled well
• Excess weight is reduced safely
• Steroid medications or other causes of insulin resistance are removed where possible
• Other health problems, such as dental disease or pancreatitis, are managed

Remission is wonderful when it happens, but it is not guaranteed. Even cats in remission still need monitoring, because diabetes can return.

What happens if diabetes is not treated?

Untreated diabetes can make a cat increasingly unwell. Over time, it may lead to:

• Ongoing weight loss
• Muscle loss
• Weakness
• Dehydration
• Poor coat and reduced grooming
• Nerve damage affecting the back legs
• Increased risk of infections
• Diabetic ketoacidosis, a serious and potentially life-threatening emergency

Treatment gives us the best chance of getting your cat comfortable, stable, and back to enjoying normal cat things, such as demanding food at inconvenient times and judging everyone from a windowsill.

Your role at home

You do not need to become a mini-vet overnight. Your main jobs are to:

• Give medication exactly as instructed
• Keep feeding consistent
• Watch appetite, thirst, urination, energy, and weight
• Keep recheck appointments
• Contact the clinic if your cat seems unwell
• Never change insulin doses unless your vet has advised it

A simple notebook or phone note can be very helpful. Record appetite, water intake if possible, litter tray changes, medication given, and any unusual behaviour.

The big-picture message

Diabetes in cats is serious, but it is also manageable. With the right treatment plan, regular monitoring, and good communication between you and the veterinary team, many diabetic cats live comfortably with few or no signs.

The aim is not to chase perfect numbers every day. The aim is a cat who feels well, eats well, maintains a healthy weight, and enjoys life.