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)

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

10 British Cat Breeds: An Overview (With Info & Pictures)

The British may be known for their staunch tradition, but they’re also pioneers of progressive breeding techniques that have produced some incredible British...

Cyril’s Purring Repertoire: 6 Different Purrs & Their Meanings

Hi, I’m Dr. Karyn! Read my introduction to learn more about me and meet my five hilarious cats: Clutch, Cyril, Alex, Zelda, and...

8 Amazing DIY Cat Wheelchair Plans You Can Build at Home (With Pictures)

Cat wheelchairs are extremely helpful for cats needing physical therapy or living with permanent disabilities. However, they can be pretty expensive, especially if...

How to Trim Cat Nails at Home: Vet-Approved Steps, Tips, & Advice

Grooming your cat is an important part of being a responsible pet owner, and nail trimming is a step that should not be...

More related

World Stray Animals Day 2026: When It Is & How to Participate

April 4th, 2024 is World Stray Animals Day, a day dedicated to increased awareness of stray animals the world over and the problems...

Clear the Shelters 2026: Origin, How It Works, Success Stories & FAQ

Animal shelters are crucial in caring for abandoned and surrendered pets, providing temporary refuge until they find permanent homes. However, overcrowding and limited...

Can a Cat Get Pregnant if She’s Not in Heat (What You Need to Know!)

If your cat has not been spayed, you may be concerned that you’ll soon have to deal with a pregnant mother and, eventually,...

Feline Idiopathic Cystitis in Cats: Signs, Causes, and Care

Urinary tract diseases are fairly common in cats, so it’s important for cat owners to be well-informed about this area of cat health....

Keep reading

Can Cats Eat Waffles? Vet-Reviewed Facts & FAQ

Did your cat take a sneaky nibble from your breakfast? Don’t panic: a bite out of a waffle now and then isn’t going to hurt your feline friend. Cats can eat waffles without severe side effects, so there is no...

Can Cats Eat Waffles

When to Euthanize a Cat? Vet-Reviewed Factors & FAQ

Watching a beloved family pet get old can be hard. As cats age, they will grow weaker and skinnier. Their behavior might change. They might not be the same cat that you used to know when they were younger. In...

a sick siberian cat being carried by owner

Why Is My Cat Standing on His Hind Legs? Possible Reasons & When To Be Concerned (Vet-Verified)

It’s not uncommon for cat owners to catch their cats doing crazy things, like chasing their tails or staring wide-eyed into the distance. If you caught your cat standing on their hind legs, you may wonder what alternative universe you...

calico-cat-having-treats

What Are E-Collars for Cats? Vet-Reviewed Types, Pros, Cons & FAQ

You may not immediately recognize the term “e-collar,” but you’ve definitely heard of them. You might know the e-collar by its more affectionately referred to term: the Cone of Shame. E-collars, or Elizabethan collars, as they’re more officially known, is...

cat wearing an ecollar

9 Interesting Cat Kidney Facts

Cats entertain us with acrobatic moves and amusing behavior, and some cat owners may believe that their strange pets come from another planet. Although felines seem alien to us, they’re more similar to humans than you may think. For instance,...

tabby cat at vet clinic

Is Patchouli Safe for Cats? Vet-Reviewed Health Facts

Humans have used essential oils for eons—as long ago as 4500 B.C. in Ancient Egypt, where they were used in ointments and cosmetics. Today, essential oils are used as part of aromatherapy and to help with minor health conditions. But...

Patchouli Flowers

Can Fleas Kill a Cat? Vet-Approved Facts & Safety Guide

Fleas are an annoying part of cat ownership. Unfortunately, your cat will likely get at least one flea infestation at some point during their life. Keeping on top of regular flea treatments should protect your kitty from harm even if...

Cat with fleas

Can Cats Eat Avocado? Vet-Verified Health Concerns & FAQ

Avocados have several nutritional benefits for humans; they are low in sugar and packed with healthy vitamins and minerals. They are considered great for heart health and may help lower inflammation. Avocados can be made into dips like guacamole, added...

Can Cats Eat Avocado