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.

Do Cats Need to Fast Before Having Surgery? What You Need to Know!

Written by: Kit Copson

Last Updated on May 2, 2024 by Catster Editorial Team

cat and vet

Do Cats Need to Fast Before Having Surgery? What You Need to Know!


Dr. Paola Cuevas Photo


Dr. Paola Cuevas

MVZ (Veterinarian)

The information is current and up-to-date in accordance with the latest veterinarian research.

Learn more »

When a cat needs surgery, owners have several questions about how they can prepare them for the upcoming procedure. One of the most common questions is about fasting before surgery. In short, cats typically do need to fast before surgery and the length of time spent fasting may vary depending on the procedure or how old the cat is.

In this post, we’ll answer all your burning questions about fasting before surgery.

3 cat face divider

Why Do Cats Need to Fast Before Having Surgery?

Cats with a full stomach are more likely to experience gastroesophageal reflux—the regurgitation of food—while under anesthetic. So, cats are required to fast before surgery because it reduces the risk of your cat vomiting under anesthetic, which can be dangerous if the cat then aspirates the vomit into their lungs.

neutering cat on a vet's operating table
Image Credit: Simon Kadula, Shutterstock

How Long Do Cats Need to Fast Before Surgery?

The standard length of time for which cats need to fast before surgery used to be 12 hours, but these days, it’s typically around the 6–8-hour mark. In some cases, food is only withheld for around 4 hours. As we can see, this is no cast-iron rule.

Moreover, the fasting requirements differ for kittens. Kittens are usually allowed a small amount of food 1 or 2 hours before the surgery—about a teaspoon for kittens under 4 pounds. Cats with diabetes may also be allowed a small amount of food.

Because the length of time and requirements vary, it’s always best to follow your vet’s advice on how long your cat or kitten should fast for.

What If My Cat Fasted Too Late or Too Soon?

Perhaps you forgot to fast your cat or mixed up the length of time your cat was supposed to fast before their surgery. It happens, but it isn’t the end of the world. Based on information from Riverview Animal Hospital, if your cat has fasted too soon, the clinic feeds them a half or a full tablespoon of food to coat the stomach a couple of hours before they undergo the procedure.

If the cat has fasted too late, the clinic asks that you arrange to have the surgery time altered to make sure your cat has fasted for the appropriate length of time to ensure a smooth surgery. It seems that the best thing to do if your cat has fasted too soon or too late is to communicate with your veterinary clinic as soon as possible.

owner feeding his cat
Image Credit: Jaromir Chalabala, Shutterstock

Can Cats Have Water While Fasting?

Cats can have water overnight while fasting, but you’ll need to take it away at least 2 hours before the surgery. It is also advised to keep your cat indoors overnight while they’re fasting, as they may find food outside or not come back in time for the surgery. Provide a litter box in the house if your cat is used to staying out at night.

cat paw divider

Final Thoughts

To recap, cats need to fast before surgery to minimize the risk of vomiting and possibly breathing vomit into the lungs. If you have any questions about fasting or aren’t sure how long your cat should fast before surgery, please contact your veterinary clinic for the specifics. Also, if your cat has fasted too soon or too late, please communicate this to the clinic.

Featured Image Credit: Stock-Asso, Shutterstock

Get Catster in your inbox!

Stay informed! Get tips and exclusive deals.
Catster Editors Choice Badge
Shopping Cart


© Pangolia Pte. Ltd. All rights reserved.