TL;DR
When is your cat’s vomiting more than a hairball? According to Dr. David MacDonald of Doylestown Veterinary Hospital & Holistic Pet Care, occasional vomiting may be common in cats, but it isn’t normal, even when it happens only once a week or once a month. A hairball is the most benign explanation, but vomiting can also point to something swallowed that shouldn’t have been (like thread, string, or small household items), a food sensitivity, pancreatitis, inflammatory bowel disease, or conditions outside the digestive tract altogether, such as liver disease, kidney disease, diabetes, or thyroid disease. Because cats hide illness well and may not act sick, Dr. MacDonald recommends raising any pattern of vomiting with your veterinarian so they can investigate with a physical exam, X-rays, or bloodwork.
You hear it before you see it. That low, guttural rumble from the other room. The dramatic heave. The hack, hack, hack. The last-minute move from the linoleum kitchen floor to the living room carpet (because why not?). And then, a few moments later, a surprise. Just for you.
The hairball is practically a rite of passage for cat owners. It’s the star of countless memes. It’s a go-to gag for cartoon cats, who cough one up for comic effect right on cue. We’ve shrugged it off with a laugh and a paper towel so many times that we don’t ever think of it as a red flag. We think of it as a punchline.
But according to Dr. David MacDonald, DVM, CVA, CVSMT, that punchline may be hiding something. Dr. MacDonald is a holistic veterinarian specializing in nutrition and integrative therapies at Doylestown Veterinary Hospital & Holistic Pet Care, and when it comes to cats and vomiting, he isn’t laughing.
Common Doesn’t Mean Normal
Most cat owners will deal with food coming back up at some point. But that doesn’t mean it’s A-OK, Dr. MacDonald says.
“It’s something many cat owners will experience, that is — the food coming up. But I don’t think we should consider any of that normal.”
His reasoning? How the digestive system is designed to work.
“It’s a directional thing,” he says. “Everything goes in the same direction. So, when something causes it to go the other way and come up as spit-up or vomit, we need to recognize that it’s not something that’s supposed to happen.”
Did They Eat Something They Shouldn’t Have?
One of the first things a veterinarian attempts to pinpoint is whether something is physically upsetting a cat’s stomach. Sometimes it’s food that doesn’t agree with them.
“Animals have a sensitivity where they don’t tolerate certain foods. That can make them feel sick or nauseous.”
Other times, it was never food at all.
“There’s always the possibility that they swallowed something they shouldn’t have. For cats, is it a piece of a toy? Is it a household item like a hair tie or an elastic band or a string from a shoelace or a sewing thread? Any of those things they shouldn’t eat.”
Dogs get most of the attention when it comes to holiday hazards like chocolate, and with the holidays bringing all manner of new temptations into the house, cats have a talent for finding trouble, too.
“It’s much more common for a dog to eat half of your shoe,” Dr. MacDonald says. “Cats typically don’t do things like that. But every now and then, they will. I remember one cat that ingested a screw. You can never rule it out. It’s always a possibility.”
The Trouble with Thread
One common troublemaker for cats is what Dr. MacDonald calls a linear foreign body — any long, thread-like material that goes down a bit too easily, then has nowhere else to go.
The scenario he describes is one no cat owner wants to picture.
“If, say, your cat gets into your sewing kit, and they start to nibble on a piece of yarn or thread… It’s like swallowing spaghetti. It goes in a little bit and then a little bit more, and they just keep swallowing longer and longer pieces. And at the end is sometimes a sewing needle. That truly does happen, and I’ve seen bad situations.”
And the signs don’t always show up right away.
“If the thread or needle gets stuck anywhere, symptoms can show up immediately or within minutes, or it could be an hour later or even the next day. We need to do a bit of detective work to figure out what they may have ingested that causes the vomiting.”
When It’s Not Something They Swallowed
Other times, nothing is stuck at all. The cause is medical.
“The other possibility is that some cats will vomit because of a medical problem. And that can be a number of things. Maybe they have a food sensitivity, like an intolerance to chicken. Or they may have some sort of irritation in the stomach or intestines that is causing them to feel sick and nauseous.”
Pancreatitis is one example.
The pancreas, while part of the digestive system, isn’t part of the stomach. It’s where digestive enzymes are mixed with food right after it exits the stomach. Occasionally, cats can be subject to stimulation that makes them produce an overwhelming amount of enzymes.
“It’s like turning the dial up to 10,” Dr. MacDonald says. “It’s too much for them to handle.”
In other cases, the culprit is inflammation that builds slowly, sometimes classified over time as inflammatory bowel disease or irritable bowel syndrome.
“Anytime that an animal is vomiting, it may not be because they ate something bad or that there’s something stuck somewhere, but that there’s inflammation which can develop over time. And it doesn’t develop in a minute.”
Vomiting Isn’t a Quirk
This is where Dr. MacDonald’s message hits home for many cat owners. The vomiting that’s easiest to ignore? It typically recurs on a regular, though not alarming, basis.
According to Dr. MacDonald, many pet owners report that their cats vomit every week. Not necessarily with every meal, or even every day – but predictably enough that it seems commonplace.
“I would still say that’s not normal,” he stresses. “We shouldn’t just accept ‘Fluffy is a cat who vomits sometimes.’ There’s a reason why that’s happening.”
To complicate things, a cat who vomits regularly may look perfectly fine on the outside.
“Cats who are vomiting semi-regularly may not even act like they’re sick,” Dr. MacDonald says.
In many cases, the cause is not in the digestive tract at all, but “something in their body that makes them feel nauseous.” Liver disease, kidney disease, diabetes, and thyroid disease are all medical conditions with symptoms that show up in the stomach (even if they don’t originate there).
And What About Hairballs?
Don’t worry. Hairballs haven’t been cleared of all charges. They just rarely tell the whole story.
“Hairballs are one reason cats vomit, and that’s probably your most benign cause,” Dr. MacDonald says.
But even a hairball can have a backstory.
“Even then, if cats are excessively licking and grooming themselves, to the point that they’re swallowing a lot of hair, there may be a problem there, too. Maybe the cat is very itchy, or they may be licking at their belly because it’s uncomfortable.”
One telltale sign is a bald spot on the belly.
“In my opinion, that usually means there’s something that is causing them to want to lick that area… Cats will lick at themselves because they know inside it feels weird, and they’re trying to soothe things from the outside.”
What to Expect at the Vet
Because the cause isn’t always obvious, the first step is a thorough look at the whole patient.
“It requires a vet to feel their belly carefully. Is there something that feels swollen or uncomfortable, or that every time you touch it, they wince? Are other diagnostics necessary? X-rays are always helpful. Are they blocked up? Are they constipated?”
From there, the goal is action, though not always the kind that comes in a pill bottle.
“Treatment could include a diet adjustment, or a closer look at imbalances with their gut health and their microbiome.”
The Bottom Line
Dr. MacDonald’s takeaway is simple: don’t let a stereotype do the thinking.
Cats are masters at hiding discomfort and pain. Vomiting may be the only clue that something’s awry.
“With cats, it’s so easy to blow things off and say, ‘It’s not a big deal. It’s just one of those things they do,’” Dr. MacDonald says. “But I think you always need to take that seriously and say, ‘That’s not normal. Let’s see if we can figure this out.’”
So, laugh at the memes if you must.
Cheer on the cartoon cat and his quest to christen the Persian rug.
Just don’t let the punchline stop you from asking more serious questions.
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FAQs
When is my cat’s vomiting more than a hairball?
Dr. MacDonald says vomiting should never be considered normal for a cat. Hairballs are the most benign cause, but regular vomiting can signal something else, such as a swallowed object, a food sensitivity, or an underlying medical condition. If it’s happening on a pattern, it’s worth a conversation with your vet.
Is it normal for my cat to vomit once a week or once a month?
Not according to Dr. MacDonald. Even if it isn’t every day or every meal, vomiting on a routine schedule shouldn’t be brushed off as “just something they do.” There’s a reason it’s happening. A medical exam can help find it.
What can cause a cat to vomit?
Causes range from hairballs and food sensitivities to swallowed non-food items, pancreatitis, and inflammatory bowel disease. Vomiting can also be a symptom of conditions outside the digestive tract, including liver disease, kidney disease, diabetes, and thyroid disease.
What is a linear foreign body?
It’s any long, thread-like material a cat swallows, such as yarn or sewing thread. Dr. MacDonald says cats can keep swallowing longer and longer pieces, sometimes with a sewing needle at the end. Symptoms can appear within minutes or as late as the next day.
How will my vet figure out why my cat is vomiting?
Expect a careful medical exam, including feeling the belly for swelling or discomfort, and possibly X-rays or blood tests. Treatment doesn’t always mean medication. It may involve a diet adjustment or a closer look at gut health and the microbiome.
