Cat Diarrhea and Vomiting: Causes and When to Go to the Emergency Vet

Dr. Mollie Powell

May 19, 2022

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Is your cat having diarrhea or vomiting? Are you concerned about what could be causing these symptoms? Do you want to know whether or not they constitute an emergency for your feline friend?

Vomiting and diarrhea can be concerning symptoms for cats, and it’s important to get to the bottom of them as soon as possible. Sometimes, both symptoms will clear up on their own in a short while. However, there are some situations that require emergency vet care. Read through the article below to find out more about both.

If you’re ever concerned about your cat’s health or behavior, you should always consult with an emergency vet to make sure everything is okay with your pet. Even if the cause of their behavior isn’t something that requires immediate care, it’s important to be on top of your pet’s health and know for sure.

6 Causes of Cat Diarrhea and Vomiting

If you notice that your cat is having diarrhea and is vomiting, you should know the common causes that can lead to your cat doing this. If you know the cause of your pet’s behavior, then you can determine if they’ll need veterinary care.

6 common causes of cat diarrhea and vomiting include:

1. Hairballs

Hairballs are one of the most common causes of vomiting in cats. When your cat vomits and a large clump of hair comes up, too, this is a hairball. In some cats, diarrhea may accompany hairballs, but should clear up after one or two loose bowel movements.

Coughing can often be mistaken for “bringing up a hairball” in cats. If you notice your cat is often hacking or gagging without producing a hairball, she may need to be evaluated for coughing. If you’re not sure, try to get a video of the behavior to show your vet.

2. Stomach Virus

Some types of stomach viruses may cause cats to experience vomiting and diarrhea. A stomach virus is a moderate to severe problem for a cat, so your pet needs to see a vet as soon as possible if she is experiencing this type of illness.

Viral causes are most common in kittens and cats who are not fully vaccinated.

3. Food Sensitivity

Another potential cause of cat diarrhea and vomiting is food sensitivity.

If your cat eats table scraps or is given a new type of cat food or treat, she may experience some short-term vomiting and diarrhea. This may mean she is sensitive or even allergic to the food that was given to her.

Additionally, if your cat’s food is changed suddenly, without giving her a chance to get used to the new food, she may have some stomach upset for a day or two while she adjusts.

4. Parasites

Digestive parasites can cause vomiting and diarrhea in cats as well. These parasites, which are often collectively referred to as “worms,” may contribute to other symptoms including appetite changes, behavioral issues, and more. Only a vet can diagnose and properly treat digestive parasites in cats.

5. Ingestion of Toxins

Toxin ingestion is one very serious and concerning potential cause of cat diarrhea and vomiting. If a cat ingests something that is toxic or poisonous, such as poisonous plants, vomiting and diarrhea will likely be some of the first symptoms.

From there, the cat’s condition will likely deteriorate quickly, so prompt emergency vet care is crucial.

6. Intestinal Obstruction

Intestinal obstructions are also very serious. Sometimes, when cats are playing, they may accidentally swallow parts of their toys or other small items they find around the home. When this happens, the item can easily cause a blockage in the intestines, which may lead to die-off of the rest of the digestive system. This problem can quickly become fatal.

When to Go to the Emergency Vet for Cat Diarrhea and Vomiting

Now that you know some of the common causes of these symptoms, it’s important to know when cat diarrhea and vomiting warrants a trip to the emergency vet. As mentioned above, if you’re ever concerned about your cat’s health, you should always contact a veterinarian or an emergency vet if you feel your pet needs care right away.

Below are situations when you should go to the emergency vet for cat diarrhea and vomiting:

If There’s Blood in Your Cat’s Vomit and/or Stool

If your cat’s stool or vomit contain blood, go to the emergency vet. Bloody vomit or bloody stool can indicate a wide range of diseases, illnesses, and health conditions that may be leading to your cat’s other symptoms. Your vet will work with you to determine what’s wrong.

If Your Cat Can’t Keep Water Down

If your cat is unable to hold down any water, go to the emergency vet. Many times, cats who are sick and experiencing diarrhea or vomiting will not want to try to drink water. However, it’s important for you to encourage your cat to do so as much as possible. You may also want to provide some no-salt-added, onion and garlic-free liquid broth (as long as this will not further upset her stomach) to help her get the fluids she needs.

If your cat is unable to hold down fluids at all, or if she refuses to try to drink any in the first place, she needs to see an emergency vet. Dehydration can become fatal in a very short time for cats, and your pet will likely need to be treated for dehydration before tackling the larger problem.

If Your Cat is Unresponsive

If your cat is unresponsive due to cat diarrhea and vomiting, you should go to the emergency vet right away. Unresponsiveness is a clear indication that your cat is experiencing a major health crisis. If you find that your cat is becoming less responsive throughout her bout of diarrhea and vomiting, even if she is still conscious, this is also a sign that she needs to see an emergency vet.

If Your Cat is Having Diarrhea or Vomiting for More Than 12 Hours

If your cat’s diarrhea or vomiting last longer than twelve hours, or if they are nearly uncontrollable, go to the emergency vet. Diarrhea and vomiting that last this long can quickly lead to severe, even fatal, levels of dehydration.

Your cat will need fluids to stabilize her, and then will need to be properly examined and diagnosed by your vet to find out what’s going on. She may need to stay overnight for treatment.

If Your Cat Has Not Eaten in Over 24 Hours

Cats experiencing gastrointestinal upset from many causes may be unwilling to eat. In addition to the risk of dehydration, prolonged periods without eating can lead to serious health issues like liver disease. 

Generally, a veterinarian will recommend tests to find the cause of symptoms, and medications such as appetite stimulants and anti-nausea medicines to help them feel better.

If Your Cat Ingested Something Toxic

If you know or suspect your cat has ingested a toxin or foreign object, go to the emergency vet. If you saw your cat eat the toxin or object, or if you have a good reason to believe this is the cause of her diarrhea and vomiting, you must respond quickly with prompt medical intervention.

Come to VEG for Your Cat’s Diarrhea and Vomiting

Understanding when your cat’s vomiting and diarrhea are emergencies and when they’re not can help you make the right decisions about your pet’s medical care. Remember, too, that if you ever have any concerns or feel like your pet is having a crisis, you should go to the emergency vet as soon as possible.

When it comes to caring for your pets, it’s important to trust your gut instinct. Any time you’re in doubt, contact your regular vet or go straight to an emergency vet’s office for professional assistance.

If you’re concerned about cat diarrhea and vomiting, or if you have any other questions about your pet’s health, call or bring your cat in to any of our VEG locations. With locations all over the country, we have emergency veterinarians available 24/7 to help guide you in the best direction and make sure your cat receives the care they need.