The 4 Most Common Causes of Vomiting in Cats—and How to Help

3 min read

If you’ve ever owned a cat, you’ve probably seen them vomit at least once (or more often than you’d like). While the occasional hairball is usually harmless, frequent or severe vomiting can signal a deeper health issue that needs attention.

In this post, we’ll break down the four most common causes of vomiting in cats, what signs to watch for, and when to call your veterinarian.

1. Hairballs (Trichobezoars)

Cats are meticulous groomers, and in the process, they swallow loose fur. Most of the time, that fur passes through the digestive tract without issue—but sometimes it clumps together in the stomach and is vomited up.

Signs it’s a hairball:

• Long, cylindrical clumps of fur in the vomit

• Occasional gagging or hacking before expulsion

  
  

What to do: Brush your cat regularly to reduce shedding and consider a hairball-control diet or supplement. If your cat is struggling to pass a hairball or seems lethargic, see your vet.

2. Dietary Indiscretion

Cats may be picky eaters, but they can still get into things they shouldn’t—whether that’s spoiled food, houseplants, or your dinner leftovers. Sudden diet changes can also upset their stomach.

Signs it’s dietary-related:

• Vomiting shortly after eating something unusual

• Temporary diarrhea or loss of appetite

  
  

What to do: Keep toxic plants and unsafe foods out of reach. When switching foods, transition gradually over 7–10 days to avoid digestive upset.

3. Gastrointestinal Parasites

Worms and other intestinal parasites can irritate the digestive tract, leading to vomiting, diarrhea, and weight loss—especially in kittens or outdoor cats.

Signs it’s parasites:

• Visible worms in stool or vomit

• Pot-bellied appearance in kittens

• Dull coat and reduced energy

What to do: Your vet can confirm with a fecal test and prescribe a safe dewormer. Regular parasite prevention is key for keeping your cat healthy.

4. Underlying Medical Conditions

Chronic vomiting can be a symptom of more serious health issues such as kidney disease, hyperthyroidism, pancreatitis, or gastrointestinal inflammation.

Signs it may be serious:

• Persistent or frequent vomiting over several days

• Weight loss, increased thirst, or changes in appetite

• Vomiting blood or bile

What to do: Seek veterinary care promptly. Early diagnosis and treatment can make a big difference in outcomes.

When to Call the Vet Immediately

🚨 Vomiting accompanied by lethargy, dehydration, blood, or sudden changes in behavior should be treated as urgent.

Bottom Line: While occasional vomiting isn’t always cause for alarm, frequent episodes or other concerning symptoms warrant a vet visit. Identifying the cause early can help your feline friend recover quickly and avoid more serious complications.

💡 Tip: Unexpected vet bills can add up quickly. If your cat is prescribed medication, check prices at local pharmacies using a pet prescription discount card—you might save 50% or more compared to vet clinic pricing.