Most cats spend a considerable amount of time grooming their coats. As they do so, their hair is swallowed and may build up over time in their stomach. If the hairball doesn’t pass from the stomach, the cat will attempt to eliminate it by coughing or gagging.
Many cats have a hairball at some point in their life, but some cats, such as long-haired cats and cats that groom excessively, are especially prone to hairballs. In hairball-prone cats, frequent brushing can help reduce the amount of hair that is ingested, thereby reducing the risk of hairball formation. Feeding a special diet designed to decrease the likelihood of developing a hairball may also help.