JACK SOMMARS

It’s the moment a cat owner dreads: being jolted awake in the middle of the night by that awful sound of retching. And while you fumble for the light switch, your favorite feline deposits a hairball on your pillow.

As much as we love them, cats vomit, even hairless breeds. Hairballs are a common culprit. But vomiting can also be a sign of a potentially serious medical problem.

So when should you be concerned?

“If your cat acts normal and vomits once or twice a month, that’s probably okay,” says Eliza Sundahl, DVM, a specialist who has treated cats for more than 30 years.

To help with hairballs, she suggests frequent grooming with a comb—not a brush—to remove your cat’s dead hair.

Since nibbling on houseplants can also cause vomiting, Sundahl says to eliminate the “salad bar” if it becomes a problem. “Check online to make sure the plant your cat chewed on isn’t toxic. Easter lilies are especially dangerous,” she says.

Parasites can also cause vomiting. There are worms your cat can pick up while outside or even inside from eating a bug that has walked through some dog poop. Fortunately, these parasites can be controlled by inexpensive drugs your veterinarian can recommend.

But even if it appears to be “just another hairball” or “he ate too fast,” red flags should go up if your cat vomits frequently and behaves out of the ordinary.

“I call it ‘wilting,’” Sundahl explains. “Your cat vomits and isn’t as active as usual. He may hide under furniture or sit in a chair when he normally is pestering you at the kitchen table. His face may look pinched up, and you can tell he just doesn’t feel well. Loss of appetite and weight loss can also indicate something is wrong.”

Sundahl suggests keeping a calendar to record each vomiting incident. “Jot down if it was a hairball, food, fluid or if there was plant material in it. Then watch his behavior to see if there are any changes,” she says.

“If your cat vomits for a couple of days, then seems okay for a few weeks, but repeats that same cycle month after month, that could indicate a footprint for a more serious health problem.”

If you see these behaviors, call your veterinarian. He or she can perform a physical exam and run a variety of tests to see if there’s an underlying problem causing the vomiting, such as an infection or food allergy, or if your cat has swallowed a foreign object.

“Cats have barbs on their tongues that face backwards. So once they get stuff in their mouth, it’s hard for them to pull it out. So they just keep swallowing it,” Sundahl says.

And some of the most common, cat-enticing objects—like string, ribbons and yarn—can be fatal when ingested. “That’s one of my pet peeves,” Sundahl admits. “You see pictures of cute kittens playing with a ball of yarn. People don’t realize a little piece of yarn can act like a hacksaw inside a kitty’s tummy.”