The first time you see your cat hurl a hairball, you might be pretty worried. He'll retch and hack and try to bring it up. Then it will be there – on the rug or some other spot – in all its undigested glory.

You might think your cat is really sick, but it's really nothing serious. A hairball is just what the name says: a wad of undigested wet hair in the stomach. Usually, they are not balls at all; they are sausage-shaped and they are formed when the cat swallows too much hair after grooming. The medical name is for a hairball is "trichobezoar."

As your cat licks her fur, her raspy tongue loosens dead hair. Because the cat's tongue is a rough surface – like "kitty sandpaper" – most of the hair sticks to it and he can't spit it out. The only thing he can do is swallow it.

Most of the hair goes through the digestive tract with no problem, just like food; however, sometimes there is just too much hair to pass easily. In this case, it stays in the stomach and forms a wadded mass.

Most cats suffer from an occasional hairball, some more than others. Longhaired cats tend to swallow more hair simply because they have more of it, but shorthair breeds get hairballs, too.

Sometimes the hairball gets too big to pass and causes your cat to get sick. In severe cases surgery may be necessary to remove it. If you suspect your cat is having trouble passing a hairball have your parents call your veterinarian, especially if your cat retches for more than three days or if your cat is constipated or refuses food for more than a day.

What Can You Do?

Although there is no cure, there are some things you can do to help:

Groom your cat. Brush him and brush him and then wipe him down with a damp cloth to remove hairs missed by the brush. The more hair you can get off your cat by brushing, the less he will swallow.

Hairball products. If the problem still exists, you can also use petroleum-based products (such as Laxatone or Hairball Remedy) that act as a laxative and lubricant to help your cat pass a hairball. These products taste good to cats and can be fed in paste form. You can also put it on your cat's paws and he will lick it off.

Hairball remedy treats or food. You can also give your cat treats that contain mineral oil, such as Pounce Hairball treatment, to break up the balls. Some pet food companies now manufacture food for cats with recurrent hair or fur ball problems. Ask what your veterinarian recommends.