Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

What Happens if I Give My Cat Too Much Insulin? (Vet Answer)

Share

man administering medicine to a cat

Your cat was recently diagnosed with diabetes mellitus, and you have to give insulin injections every day. Today, you realized that you and your spouse both gave an evening dose of your cat’s insulin. What do you do? Your cat needs to be seen by your vet right away because this could result in stress hyperglycemia.

divider 2 cats

What to Do if Your Cat Gets Too Much Insulin

If you definitely gave too much insulin or think that you might have, stop, take a deep breath, and call your veterinarian’s office. If your veterinarian isn’t open or isn’t available, check for the nearest veterinary emergency hospital. If your regular vet doesn’t have overnight care, you may have to go to an animal ER anyway.

If you can’t get to your veterinarian immediately, the office might suggest you rub a sugary substance, such as Karo syrup, on your cat’s gums.1

At the veterinarian’s office, your cat will likely need blood work to perform a spot blood sugar check to see where it is. Your veterinarian will likely need to place an intravenous (IV) catheter and give your cat a dextrose solution.

Your kitty might need fluid therapy and supportive care, depending on how much insulin they received and how low their blood sugar level goes. They’ll likely need several blood sugar readings to monitor their glucose levels. If your cat has a blood glucose monitor placed, like a Freestyle Libre, so that you can monitor their levels at home, bring the monitor with you to help your vet team monitor your cat’s level.

veterinary-blood-test
Image Credit: PRESSLAB, Shutterstock

Signs of Hypoglycemia in Cats

If you’re unsure if your cat received too much insulin and you have a monitor at home, perform a spot check to see where the level is. Doing so at home should give a more accurate reading than in the vet’s office because cats can have stress hyperglycemia, where stress spikes their blood sugar level up.

Signs of low blood sugar in cats include:
  • Lethargy
  • Unsteady gait
  • Weakness
  • Loss of bladder or bowel control
  • Seizures
  • Coma

Your cat can develop hypoglycemia even if it hasn’t received a second dose or more insulin than was prescribed. If it’s lost weight, switched foods, or has other health issues, its calculated dose could be more than it needs.

Treating Diabetes in Cats

Diabetes is a fairly common condition in cats. The Cornell Feline Health Center estimates that 1 in 100 to 1 in 500 cats will develop diabetes. Insulin is a hormone used to regulate blood sugar levels, acting as a key to moving glucose in the bloodstream (a simple sugar) into the cells to be used as an energy source.

The most common way to treat diabetes in cats has been insulin injections. There are several different insulin products, and they may be short-acting, intermediate, and long-acting insulin. Your cat might need injections every 12 to 24 hours.

There are newer oral medications that have recently come out to treat diabetes in cats, such as Bexacat.

Factors That Influence Diabetes in Cats

Diet

Cats are obligate carnivores, and their bodies are not designed to eat a lot of carbohydrates. Unfortunately, the mainstay of many of our cat’s diets is dry kibble, which tends to be full of carbohydrates. Feeding your cat quality canned food is usually better than feeding kibble and will often yield better glycemic control.

Weight

Overweight cats are more likely to become diabetic. A veterinarian can help you develop a weight loss plan to help your cat lose weight. As your cat loses weight, it will likely need less insulin.

Need veterinary advice but can't get to the clinic? Catster recommends PangoVet, our online veterinary service. Talk to a vet online and get the answers and advice you need for your cat without having to leave your living room — all at an affordable price!

PangoVet_Mention-in-Content for PangoVet2 save money

Exercise

More active cats are usually less likely to be overweight. Physical inactivity is also associated with diabetes.

Other Factors

Male cats are more likely to become diabetic. Your vet may utilize medications that increase the likelihood of diabetes, such as steroids. These medications may be used for conditions such as autoimmune issues and asthma.

A cat having a check up at a small animal vet clinic
Image Credit: Tyler Olson, Shutterstock

Preventing an Insulin Overdose in Cats

One of the best ways to prevent an insulin overdose in your cat is to keep a log of it. You can record when insulin was given each day. If you have a glucometer at home, you can also track your cat’s activity, appetite, and blood sugar level.

Consider having one person responsible for administering insulin. If a limited number of people are in charge of giving your cat insulin, you’re less likely to double up administering it. Make sure your cat eats its food before administering insulin. If your cat isn’t eating normally, contact your veterinarian for guidance. The veterinarian might recommend a physical exam for your kitty to check for underlying issues or suggest a lower dose of insulin.

Insulin comes in two main concentrations: 40 units per milliliter and 100 units per milliliter. Syringes are also of different sizes. Make sure you double-check the dosage you are giving and the syringe each time you get a new prescription. If your veterinary team or pharmacy switched up syringes, it’s easy to make a mistake in dosing.

divider 2 cats

Frequently Asked Questions (FAQ)

How long does an insulin overdose last?

The duration of an insulin overdose can depend on several factors, particularly the type of insulin and how your cat was acting when your veterinary team intervened. In most cases, longer-acting insulin will take longer to get over than short-acting. If your cat was relatively asymptomatic, it should be back to normal quickly, but if it’s having significant issues such as seizures, it may take several days to recover, if at all.

How much is too much insulin for a cat?

Your veterinarian will need to prescribe insulin for your cat. The dosage calculations vary slightly depending on the type of insulin used, but the typical starting range is 0.25 to 0.5 units per kilogram of body weight every 12 hours.

owner administering insulin to her cat
Image Credit: Elena Vorman, Shuttestock

divider 2 cats

Conclusion

If you think your cat might have received an overdose of insulin, contact your veterinarian immediately or a local veterinary emergency facility. Your cat will likely need supportive care and dextrose supplementation until they stabilize.


Featured Image Credit: Jane Nadezhina, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Why Chicken Bones Are More Dangerous for Cats Than Most Parents Realize

Chicken bones seem harmless enough, but for cats, they can cause serious damage quickly. Whether your cat swiped a piece off the counter...

Fantastic Pet Pantries and Where to Find Them

Let’s face it: times are really tough right now, and those of us in the 99% are struggling with the cost of just...

Ask Dr. Paola – Help! My Cat Refuses to Drink Water! (April 13, 2026)

Welcome to our “Ask Dr. Paola” series, where every Monday we bring expert advice straight from Dr. Paola Cuevas (MVZ) to help our...

Why Healthy Cats Still Vomit Sometimes (And How to Respond)

A cat that just vomited needs a specific kind of care, and the feeding decisions you make in the next few hours actually...

More related

Bombay Cat Health Problems: 5 Common Issues

The Bombay Cat is an adorable medium to large cat with sleek and short black hair. They’re a mix between the Burmese and...

25 Top Cat Blogs Every Kitten Lover Should Read in 2026

Cats are loved by the internet and have become a staple in internet culture. While cat videos are the most popular form of...

Why Do Cats Sleep at the Foot of the Bed? 8 Possible Reasons for This Behavior (Vet Reviewed)

Of all the strange things cats do, why do they choose to sleep at your feet instead of snuggling at your chest at...

Cat Airplane Ears: 4 Vet-Verified Reasons Why Cats Do This, Facts & FAQ

Cats are known for their quirky behaviors, but one that continues to baffle pet owners is when they have “airplane ears.” This seemingly...

Keep reading

Are Cats Playful? Vet-Reviewed Feline Character Explained

Absolutely, most cats love to play! However, cats vary a lot in temperament depending on their breed, gender, and other factors. Some breeds are particularly known for being playful, like the Bombay, while others are known for not being playful....

Two cats are lying on the floor. Gray cats are playing with a laser pointer.

9 Best Cat Meal Toppers in 2026 – Reviews & Top Picks

Disclaimer: Before changing your cat’s food or offering new ingredients, consult with your veterinarian. Pets that are on a prescription diet or suffer from certain ailments may need to avoid certain food ingredients.Caring for a cat certainly has its ups...

Grey domestic cat being given food in a bowl

How to Choose Your Second Cat: Vet-Approved Tips for Finding a Great Friend for Kitty

If you currently have a cat and are planning to add another to your family, there are several critical factors to consider and steps to take before you can bring your new feline companion home. Once you’ve thought things through,...

two cats playing

Can CBD Help a Cat With Anxiety? Exploring Alternatives

There have been no scientific studies that investigate the impact cannabis has on pets, but many pet parents are turning to it for help with their cat’s anxiety. And yes, it does work. When considering CBD for your pet, the...

Man giving CBD oil to a cat

How to Make a Cat Live Longer: 6 Vet Approved Tips

It’s hard to think of a world without your beloved cat, which is why you might be willing to try just about anything to help your cat live longer. Most cats have a lifespan of 13–17 years, but with the...

tabby cat sitting on the jute wicker rug

Is a Humidifier Safe for My Cat? (Potential Risks & Crucial Safety Tips)

For certain households, using a humidifier is a necessity during the winter months. But maybe you have a new cat or are thinking about purchasing your first humidifier and are not sure if it will be safe with your cat....

Catster_is a humidifier Safe for Cats TEMPLATE_v1_Feb 28 2025

Can Cats Eat Gravy? Nutritional Facts & FAQ

Like humans, cats enjoy a good meal. And while many people might think that all cats only eat dry food, that is not the case. Many cats love gravy, and several wet foods are made with gravy; some even have...

Can Cats Eat Gravy

Do Feral Cats Like Catnip? Vet-Approved Facts & FAQs

If you’ve ever watched a cat go crazy over catnip, you may be surprised to learn that some cats are completely indifferent to it. However, feral cats, house cats, and even large wild cats, such as lions, leopards, jaguars, and...

cat smelling catnip

Love Cats? So Do We! Join the Catster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Catster Email Newsletter

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.