Diabetic Cats: Insulin, Home Monitoring and Diet Day to Day

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

A diagnosis of diabetes can feel overwhelming, with injections, tests and rules. The reassuring news is that many owners are surprised how quickly the routine settles into daily life, and many diabetic cats regain weight and energy. This guide covers day-to-day management. See diabetes in cats for the disease basics.

The goal

Insulin lowers blood sugar. The aim is to keep glucose in a safe range, without dropping too low, so signs such as thirst, urination and weight loss go away. That is done through insulin, diet, routine and monitoring, working with your vet.

Giving insulin

• Your vet prescribes the type, dose and timing, usually twice daily, about twelve hours apart. Never change them yourself.
• Use the right syringe for your insulin, since concentrations differ. U-40 syringes go with U-40 insulin, and U-100 syringes go with U-100 insulin, and some pen devices are made for cats.
• Mix the bottle as the label says, and keep it as directed.
• Give the injection in a loose fold of skin, over the scruff, shoulder or flank, rotating sites.
• Give the injection after your cat has eaten, or while it eats, so that you know it is eating.
• Reward afterwards with praise or a treat.

Your clinic will teach you, and watch you practice. If your cat flinches or a few drops leak out, do not give a second dose. Note it in your log, and call your vet if unsure.

The routine

Consistency matters. Feed and inject at the same times each day, and keep meals and exercise steady. Keep a log with date, time, dose, appetite, water intake, urine amount, energy and any problems.

Home monitoring

• Weight and water intake. Weigh weekly, and watch the water bowl.
• Urine glucose and ketone strips. Some owners check urine, particularly if the cat seems unwell. Ketones are a warning of a dangerous complication called diabetic ketoacidosis.
• Blood glucose checks. Many owners learn to take a drop of blood from the ear or paw, with a glucometer made for cats. It lets your vet see how the glucose changes through the day. A glucose curve, done at home, is often less stressful than in the clinic.
• Continuous glucose monitors, small sensors on the skin, are increasingly used in cats, and reduce the number of finger pricks.
• Fructosamine tests, at the vet, show the average over a couple of weeks.

See cat blood tests explained.

Diet

Many vets recommend a high-protein, low-carbohydrate wet food. Studies show that cats on such diets are more likely to go into remission, and have lower insulin needs. Switch gradually, and only with your vet's advice, since insulin doses may need to be reduced. Feed consistent portions, and avoid treats high in carbohydrates. Help your cat stay at a healthy weight. See wet vs dry cat food, how much should I feed my cat and how to help an overweight cat lose weight.

Low blood sugar (hypoglycemia)

Too much insulin, too little food, vomiting or excess exercise can cause hypoglycemia. Signs include weakness, wobbling, glassy eyes, hunger, trembling, twitching, seizures and collapse. It is an emergency.

• If your cat is alert and can swallow, offer food. Ask your vet in advance about rubbing a small amount of corn syrup or honey on the gums.
• If your cat is seizing or unresponsive, do not put anything in its mouth. Rub a little syrup on the gums, and go to the vet immediately.
• Do not give the next insulin dose until you have spoken to the vet.

Discuss your plan with your vet beforehand.

When your cat is not eating

A diabetic cat that does not eat can drop its blood sugar if given full insulin. Ask your vet what to do if appetite drops. Many advise to give half the dose or none, and call. Do not guess.

Remission

Some cats, particularly those diagnosed early and fed low-carb diets, can stop insulin for months or years. Remission is not a cure, and signs can return. Continue monitoring.

Other illnesses

Pancreatitis, kidney disease, thyroid disease and dental disease can affect diabetic control. See pancreatitis in cats. Keep up regular rechecks.

Boarding and travel

Plan ahead. Find a sitter or boarding that can give insulin, and write clear instructions. See cat sitter vs boarding and preparing for a cat sitter.

When to see a vet

See a vet if your cat has low or high blood sugar signs, vomits or stops eating. Use the US vet directory to find a clinic.

This article is general educational information, not veterinary advice. Every cat is different. If your cat is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.