Feeding a cat canned pumpkin or small pieces of fruits and vegetables is a remedy for hairballs. Adding fish oil or vegetable oil to the cat's diet is helpful in treating hairballs as well.
The fiber in a teaspoon of canned pumpkin or a few pieces of apple, carrot or sweet potato administered to a cat once a day can help move hairballs through the cat's digestive system for excretion. It is best to check with a veterinarian before feeding the cat other fruits or vegetables because some are harmful or incompatible with a cat's digestive system. A small amount of fish oil or vegetable oil added to the cat's diet helps lubricate the digestive system so that any hairballs pass through more easily.