Diabetes in Cats

What is diabetes mellitus in cats?

Diabetes mellitus, commonly known as diabetes, occurs when your cat’s body does not produce enough insulin, or cannot produce insulin at all. Insulin is a hormone that allows the body to absorb glucose (sugar) from the blood. Without enough insulin, blood glucose levels become too high, and excess glucose is passed out in your cat’s urine.

What causes diabetes in cats?

Diabetes in cats has many similarities to type 2 diabetes in humans. Factors such as a lack of exercise and being overweight also increase a cat’s risk of developing diabetes.

Other possible causes include side effects of certain medications (such as prednisolone, dexamethasone and the feline contraceptive pill), excess growth hormone (acromegaly), Cushing’s disease (which is rare in cats) and problems with the pancreas.

Cats diagnosed with diabetes are usually over 7 years old, with around 75% being between 8 and 13 years of age. Diabetes is also more common in male cats than in female cats.

What are the symptoms of diabetes in cats?

A cat with diabetes passes excess glucose and fluid in its urine. You may notice that your cat starts drinking more than usual. Because glucose is an important source of energy and is lost through the urine, your cat may also eat more while continuing to lose weight. Without treatment, diabetes can eventually make your cat seriously ill.

The main symptoms of diabetes in cats are:

• Increased thirst and urination
• Increased appetite
• Weight loss
• General ill health and vomiting (in the later stages)

How is diabetes diagnosed in cats?

Diabetes can be diagnosed by measuring an elevated blood glucose level in your cat. However, stress can also cause blood glucose levels to rise, so we prefer to measure them on several occasions where possible.

If the blood glucose level is consistently too high, we will also measure fructosamine levels in the blood. This gives us an indication of your cat’s average blood glucose levels over the previous two to three weeks.

We will also always recommend more comprehensive blood and urine tests to check for other underlying conditions. For example, it is particularly important to assess whether the pancreas is functioning normally.

How is diabetes treated in cats?

Insulin preparations: ProZinc® and Caninsulin®

Your cat has a shortage of insulin. This hormone can be administered by giving injections under your cat’s skin. These injections usually need to be given twice a day.

It is important that your cat eats before receiving an insulin injection. Once diabetes has been diagnosed, we will arrange an appointment with you and your cat for an insulin injection training session. During this session, we will practise administering the insulin together and discuss your cat’s treatment plan in detail.

Treating diabetes requires a great deal of commitment and consistency from you as an owner, and we will guide and support you throughout the process.

Diet

In addition to insulin treatment, it is important to feed your cat a diet that is low in carbohydrates. The composition and quantity of the food, as well as feeding times, should remain as consistent as possible.

We recommend Hill’s m/d. If your cat tends to eat small amounts throughout the day, this can be a suitable feeding routine. However, if your cat eats its entire meal in one sitting, we may recommend offering four smaller meals a day: one just before each insulin injection and another four hours later.

Weight

Being overweight is an important risk factor for developing diabetes and can also negatively affect your cat’s quality of life. For example, it can be more difficult to regulate blood glucose levels in overweight cats.

It is therefore very important for overweight cats to lose weight. We can help you develop a suitable weight-loss plan for your cat.

Blood pressure

At least half of all cats with diabetes also have high blood pressure. This is why we always measure the blood pressure of cats diagnosed with diabetes. The procedure is completely painless for your cat.

High blood pressure can have harmful effects on several organs, including the kidneys, brain and eyes. If necessary, it can be managed with medication to lower blood pressure.

Follow-up appointments for cats with diabetes

Our aim is to relieve your cat’s symptoms, such as excessive drinking and urination and weight loss, as quickly as possible. To achieve this, we need to find the right insulin dose, which requires regular blood glucose checks.

Initially, these checks will take place once a week. Once the correct insulin dose has been established and your cat is doing well (drinking and urinating less and no longer losing weight), the frequency of these checks can be reduced.

However, regular monitoring remains essential, as your cat’s insulin requirements may change over time and the dosage may need to be adjusted. We check your cat’s blood glucose level by making a small prick in the ear. Just one tiny drop of blood is enough!

Our highly experienced veterinary nurses carry out these checks. If you would prefer your cat to be examined by a vet, please let us know.

Monitoring blood glucose levels at home

If your cat’s condition allows, regularly monitoring blood glucose levels at home, either by you or with our help, can be a good or even better way to check whether your cat is receiving the correct insulin dose. Your cat is likely to experience less stress at home, allowing us to obtain more reliable blood glucose readings.

To do this, you will need to learn how to collect a small drop of blood from your cat’s ear. Please feel free to ask us about the options for monitoring your cat’s glucose levels at home. We’ll be happy to teach you how.

Please note: Never adjust your cat’s insulin dose without consulting your vet first!

Prognosis

If there are no other underlying conditions, diabetes can be managed successfully. If treatment is started early, there is even a chance that your cat may go into remission within a few months.

With well-managed diabetes, your cat’s life expectancy can be similar to that of a cat without diabetes.

Hypoglycaemia / Low blood glucose

Low blood glucose can occur if your cat has not eaten enough (for example, due to vomiting or diarrhoea) or has been more active than usual. It may also happen if your cat’s pancreas starts producing insulin again. Unfortunately, mistakes when administering insulin can also occur.

When blood glucose levels drop too low, the brain does not receive enough glucose to function properly. This can be life-threatening. Hypoglycaemia usually occurs 2–4 hours after an insulin injection.

You may notice the following symptoms in your cat:

• Hunger at unusual times
• Restlessness or unusual lethargy
• Shivering or trembling
• Unusually deep sleep
• Abnormal movements

What should you do if you notice these symptoms?

• Offer food immediately. If your cat refuses to eat, apply glucose powder (dextrose) to the oral mucous membranes inside the mouth. The recommended amount is 1 gram per kg of body weight (for example, 5 grams for a 5 kg cat). Alternatively, mix it with a little water to make a paste and carefully administer it to your cat.
• If your cat does not improve, contact us immediately for advice.
• If your cat improves, offer another meal, ideally every two hours for at least 12 hours after the insulin injection.
• Contact us to discuss the next steps. We will advise you on the appropriate insulin dose going forward.

Preventing diabetes in cats

Diabetes in cats can develop for several reasons, including obesity, side effects of certain medications, excess growth hormone, Cushing’s disease and problems with the pancreas.

The most common risk factor is obesity, which can often be prevented. A balanced diet with carefully measured portions and regular exercise are important for maintaining a healthy weight.

Would you like advice on your cat’s diet? Our nutrition expert will be happy to help!

Important points when treating diabetes in cats

Diabetes that is difficult to regulate

In some cats, we may find that blood glucose levels do not decrease after starting insulin injections. This is known as insulin resistance. There is often an underlying cause, such as a urinary tract infection, dental inflammation, an overactive thyroid gland, or possibly Cushing’s disease or acromegaly (both of which are rare in cats).

Diabetic ketoacidosis

If diabetes is left untreated for too long, your cat may develop a serious complication called diabetic ketoacidosis, in which harmful acids called ketones build up in the blood. This can make your cat very ill, causing symptoms such as weakness, lethargy, loss of appetite and vomiting.

If you notice these symptoms, it is important to bring your cat to the clinic as soon as possible. Intensive treatment is often required.

Important tips for managing diabetes

• Keep your cat’s feeding routine and physical activity as consistent as possible.
• Store the insulin vial upright in the refrigerator.
• Before first use, shake the insulin vial vigorously until the contents form a uniform, milky suspension.
• Before drawing up each subsequent dose, gently roll or invert the vial until the suspension is uniform again.

If you have any questions, please contact us or book an appointment directly!