Our pets may not be able to communicate with words, but their actions can give us clues on how they feel.

If your dog is wagging its tail, they might be expressing happiness, according to Dr. Aya Alt, the medical director of the VCA Broadway Hospital and Pet Center. On the other hand, if your dog is vomiting, this is a sign to bring them to the vet.

So what does it mean if your dog chases its tail? While some reasons are more benign than others, the behavior can signal larger health concerns, says Alt.

Why do dogs chase their tails?

On a base level, it's normal for dogs to chase their tails, explains Alt.

Tail-chasing that occurs every once in a while and a dog can be easily distracted from is "not really an issue," she says. The tail-chasing shouldn't impact a pet owner's day-to-day routine either.

It's common, especially, for puppies to chase their tails as they are becoming aware of their bodies through play.

As dogs get older, they may still chase their tails. This behavior can cause concern, however, if done incessantly, Alt says.

There could be several explanations for your dog's tail-chasing habit, she adds. For instance, certain breeds are more susceptible to the behavior. Bull terriers, for example, are "notorious" for chasing their tails, says Alt.

"We've actually discovered now that that may be related to a specific gene that they carry that makes them sort of obsess about their tails," she explains. In severe cases, some Bull Terriers will chase their tails to the point that it impedes their daily functions, like eating.

German Shepherds are another notable breed when it comes to tail-chasing because they tend to have lower back and hip issues, Alt says. This breed may chase its tail to signal discomfort or pain.

Skin issues or fleas may also cause your pet to chase its tail, as well as anxiety or stress, she adds.

In adult dogs, tail-chasing every once in a while is "no big deal," Alt says. But if there's a change in frequency, it's worth giving your vet a call, she advises.

"We have to make sure that there aren't any fleas. We might have to take X-rays or do a physical exam or even do something like an MRI to make sure that there are no underlying medical things that could be causing pain," she explains. "We have to do a full medical workup to rule out any medical causes." In these instances, medication may be prescribed to treat any mental or physical issues.

From there, veterinarians can determine that your dog's tail-chasing is compulsive.

"When it's an obsessive thing, we don't necessarily want to tell the dog 'no' or 'stop' while they're doing it because it gives them some attention, and attention, whether it's negative or positive, is still attention, and it can help reinforce that behavior," she explains.

Pet owners should try to interrupt the behavior without being direct about it, Alt advises. "That might be something like, you get up and walk out of the room because a lot of times dogs will want to follow you," she says. "You might put their harness on and go for a walk because while they're walking, they're not going to be able to turn around and chase their tail."

You can also reward behavior that isn't tail-chasing. "You might give them a treat when they're just sitting there quietly looking out the window or when they're just resting," Alt says.

If you want your dog to stop chasing its tail, you identify the cause. "Every case is so different," says Alt, and veterinarians can help assess your dog's behavioral change.