How much Kitty Vomit is too much?

Vomiting and hairballs are normal once or twice a month - but not more

June 23, 2014 (published)

Photo by Dr. Teri Ann Oursler

"My feeling is that one or two vomits per month means that you are a cat."

Oh yeah, baby.

Dr. Jeff Latimer posted his sentiment about cat vomiting/hairball frequency in a message board of the Veterinary Information Network (VIN), an online community for veterinarians. "If it is more than this, or if it is increasing, there is likely some low-grade chronic cause, that if we find and fix, we are minimizing the chance for malignancy in the future."

If a cat is tossing up hairballs with wild abandon, there is more going on than most cat owners realize.

Dr. Latimer asked for the opinion of other veterinarians: "If you have a cat who has five hairballs per month all year long, do you want to work him up?"

Even veterinarians are not exactly sure how much hairball tossing is copious or just a bit much, or when something should be done about it.

Feline specialist Dr. Michele Gaspar said that in her opinion it seems as though more colleagues are tuning in to the fact that cats are not a "normally vomiting species." (Although most clients aren't aware of which species would cozy up to a Roman vomitorium, vultures seem to regularly don togas in preparation.)

If one of Dr. Gaspar's feline patients is having one or two episodes - or more - of vomiting a month, with or without hairballs, she discusses with the client that this frequency is actually abnormal; some of us have become too accustomed to stepping in something disgusting, usually with bare feet, and we just deal with it. In a younger cat, she recommends a dietary change and avoiding beef, lamb, and seafood as a conservative measure. In older cats, she gets more aggressive with suggesting diagnostic blood work and a urinalysis. If the cat has lost weight, no matter what the age is, she recommends further testing.

She used to work with a boarded internist whose motto was that "hairballs aren't due to a grease deficiency," so she does not use petroleum-based hairball prevention products.

Dr. Gaspar thinks it is critical to differentiate between regurgitation and vomiting; unfortunately, most clients can't tell the difference. Bottom line: vomiting is a forceful ejection of stomach contents, an active effort where you can see drool and the pet's sides heave up and down - not to mention it looks nauseated - whereas regurgitation is passive and the kitty just stands and seems a wee bit surprised that undigested food is popping out of his mouth. Wanna see the difference? Feed the animated dog and watch him toss! (It's just the same for kitties.)

"I usually ask if the cat is actually vomiting up wads of fur, and how often," Dr. Victoria Sheheri said on the VIN message board discussion. A lot of hairballs isn't normal, either, especially in shorthaired cats; Dr. Sheheri says it suggests decreased gastrointestinal (GI) motility that is often secondary to GI inflammation or cancer. But usually her clients reveal that the cat is actually vomiting food or bilious contents with a small bit of fur.

"As a general guideline, more than once a month, I start to worry a bit more," said Dr. Sheheri. She generally recommends canned, low-carbohydrate, higher-protein diets for most cats, seafood-protein-free, as a general rule to try to help prevent or control GI issues. A diet change guided by a veterinarian can be a good starting point in younger cats. She finds that some cats dramatically reduce vomiting on a slow, careful change to eating only canned food. If the food is switched too quickly, owners may become discouraged by the digestive upset (and all cat owners know what that means!) apparently caused by the switch.

She asks her client at each visit how frequently the cat is actually vomiting and notes that in the medical record. If the amount of vomiting creeps up over time, it helps owners see the need for a workup.

The three cats of Dr. Christina McRae, who has a feline-only practice, provide a study in vomit. Her shorthair cat sheds the most and vomits the most, about once every two to three months; he produces two or three food regurgitations followed by a hairball over a period of one to two days. Her 21-year old cat vomits digested food slurry about once or twice a month, but is in excellent body condition and is on a high protein/low carbohydrate, canned food-only diet. "I find she vomits more when she is constipated or after drinking a lot of water. She has a fetish with the bathtub faucet," Dr. McRae said. “The middle girl, a long hair, has hairballs only when her allergic dermatitis flares up."

What this all boils down to is a reminder to cat owners that vomiting, regurgitation, and/or hairballs are normal once or twice a month, but there comes a point when it's abnormal and a cause should be searched for and treated. So if your naked feet are finding icky feline bodily fluids more often than they used to, your kitty should be examined for an underlying cause. (Bonus point: Your carpeting won't have to be replaced as often.)

Of course, cat owners can benefit from Dr. McRae's savvy accommodation:

"My husband and I chose cat-vomit-colored carpet when we redid the house several years ago. The next house will have tile with a central floor drain."

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