That moment when you witness your dog happily bounce around and pick up what looks like a rock is likely a mix of confusion and annoyance for most pet parents.

Who does that? Well, dogs.

Dogs eating rocks is actually a very common occurrence with a number of possible causes, says Dr. Adriana Fisher of VCA Animal Hospitals.

“I have seen a standard Poodle eat 10 pounds of loose gravel because frying oil was dumped on the gravel driveway,” says Dr. Fisher.

Why do dogs eat rocks? 5 common reasons

Possible reasons for dogs chewing rocks range from medical to behavioral:

• “I have seen a great deal of sled dogs that eat rocks when they are not in training season,” says Dr. Fisher.
• Pica (eating non-food items) induced by a nutritional deficiency. “But this is usually explained by a behavioral issue,” says Dr. Fisher.
• Spills on rocks from dog-enticing things like food grease or blood.
• General anxiety, separation anxiety or compulsive disorders also can cause dogs to eat abnormal objects like rocks. Dr. Fisher says compulsive and anxiety disorders usually have other symptoms like chewing on any object available, self-mutilating, tail-chasing and/or destroying items when left alone.
• A puppy eating rocks can mean teething. “Young dogs like to chew on anything to relieve their gum pain — including rocks,” she says.

How to stop your dog from chewing on rocks

“A basket muzzle is the best option for rock-eaters when they are outside,” says Dr. Fisher. “This allows them to pant and drink water but not eat rocks.”

Other ways to prevent dogs chewing on rocks include:

• Give your dog safe items to chew like bully sticks, dental chews and frozen, nonfat plain yogurt in a Kong or just as a large, frozen block, says Dr. Fisher.
• Enrich your dog’s daily activities with exercise, training and mental stimulation.
• Get your dog checked out at the vet to rule out a nutritional deficiency.
• Monitor your dog outside when rocks are present and limit access to rocks as much as possible.

When  is it an emergency?

When a dog swallows a rock or injures himself from chewing on a rock, take him right to the vet.

Chewing rocks can lead to broken teeth that need surgical removal and swallowing rocks can lead to a gastrointestinal blockage requiring surgical removal from the GI tract, says Dr. Fisher.

“If the owner knows a rock has been eaten, they should bring their dog to the vet immediately as removal via endoscopy or vomiting induction is easier if the rock is in the stomach,” she says. “Rocks can sit in the stomach for days to months and only cause some GI symptoms such as occasional vomiting and decreased appetite. Once the rock moves through and blocks the intestine, then it is a life-threatening emergency. A rock blockage can cause rupture of the intestines that can lead to death fairly quickly.”

Rock-eating in dogs is more common than you might think, but it’s still potentially dangerous. Monitor your puppy or dog if you suspect this is becoming a bad habit and determine if it’s behavioral or medical. In some cases, the solution could be as simple as more exercise and brain games.