Hairballs are a common enough thing for cats to go through — after all, they're kind of renowned for having hairballs. But that doesn't mean that it's necessarily a normal or safe thing for your cat to experience. There are a lot of things that a hairball can either do or signal that could mean bad news for your cat. Here's just a few of them.
One of the things that a hairball might mean is that your cat has a stomach blockage. This is what it sounds like; it's a wall of hair that forms in the intestines or bowels. When this happens, it blocks the body from being able to process food or produce excrement. In other words, your cat won't be able to eat or poop if they develop a blockage. This is why you should never overlook a hairball no matter how minor it seems to be.
Hairballs can potentially choke cats as they're coming up. This is because a hairball is an extremely dense object that's had the hair squashed down by the natural convulsing action of the intestines as it pushes food down. This tight ball of hair can get stuck in the esophagus, where it can block the airway if it's stopped up in the wrong place. This can not only choke your cat but potentially cut off their airway, which is extraordinarily dangerous.
The last problem your cat might have is tied to the hair, rather than the hairball itself.
When your cat produces a hairball, not necessarily all of the hair comes up. Instead, some of it can stay in the guts where it will pass out through your cat's back end. The problem with this is that if enough hair manages to pass through the guts, it can become tangled around feces, producing a similar object to what your cat vomited up. This can not only be difficult for your cat to pass, but under the right circumstances, it can get stuck partially in and out of your cat, as the tangle of hair is caught up in the intestines and won't let the feces fully out of the body.
If your cat has a hairball, it's worth at least calling a veterinarian's office like Animal Emergency Clinic for a consultation. You may be asked to bring your kitty in in order to have them screened for intestinal blockages and left-over hair that could cause health problems. If so, make sure that you bring your kitty in so that they don't suffer from the problems that often go hand-in-hand with hairballs.