If your pet has an appetite for such oddities as socks, rocks, or even feces, chances are you’ve wondered—and worried—about her unusual eating habits. In this case, your worry may be justified: Not only can your possessions be destroyed or damaged, but objects such as clothing and rocks can produce life-threatening blockages in your pet’s intestines.

Eating non-food items has a name: It’s called pica. A specific type of pica is stool eating—either the dog’s own or that of another animal. It’s called coprophagia.
Rarely seen in cats, coprophagy is fairly common in dogs, especially those who tend to be highly food-motivated. Although it’s not necessarily dangerous to the animal, it probably is unacceptable to you.

Why Animals do This

The causes of pica and coprophagy are not known. Many theories have been proposed by various experts, but none has been proven or disproven. One idea is that such behaviors may be attention-seeking behaviors. If engaging in one of these behaviors results in some type of social interaction between the animal and her owner—even a verbal scolding—then the behavior may be reinforced and occur more frequently.

Others think these behaviors may be attempts to obtain a necessary nutrient lacking in the diet, although no nutritional studies have ever substantiated this idea. Pica and coprophagy may also stem from frustration or anxiety. It’s even possible that the behaviors begin as play; as the animal investigates and chews on the objects, she eventually begins to eat or ingest them.

Some experts have suggested that coprophagy is carried over from the normal parental behavior of ingesting the waste of young offspring. Others believe that coprophagy occurs more often in animals who live in relatively barren environments, are frequently confined to small areas, or receive limited attention from their owners. It’s also possible that dogs learn this behavior from other dogs. Because pica and coprophagy are not well understood, stopping these behaviors may require assistance from an animal-behavior professional who will work individually with you and your pet.

Suggested Solutions for Coprophagy

Because the cause of coprophagy isn’t known, no techniques or solutions are known to be consistently successful. However, the following techniques may be effective in resolving the problem.

• Treat your pet’s food with something that causes her stool to taste bad. A commercial product called 4-BID™ is available through your veterinarian. The same result may be achieved by using the food additive MSG. Based on owners’ reports, both of these products work in many cases, but not all. Before using either of these products, consult with your veterinarian.
• Give your pet’s stools a bad taste by sprinkling them directly with cayenne pepper or a commercial product such as Bitter Apple®. For this method to be effective, every stool your pet has access to must be treated so that she learns that eating stools results in something unpleasant. Otherwise, she may discriminate (using scent) which stools have been treated and which have not.
• Keep your dog on a leash any time you take her outside. If you see her about to ingest a stool, interrupt her by clapping your hands, spraying a squirt bottle, or shaking a can (only for pets who aren’t afraid of loud noises). Then immediately give her a toy to play with instead, and praise her for taking an interest in the toy.
  Clean your yard daily to minimize your pet’s opportunity to eat her stools.
• If your dog eats cat feces from the litter box, install a babygate in front of the litter box area. Your cat shouldn’t have any trouble jumping over it, but your dog may not make the attempt. Or place the litter box in a closet or room where the door can be wedged slightly open from both sides so that your cat has access but your dog doesn’t.
• Think twice before setting up a booby trap to stop your dog from eating cat feces from a litter box: If it frightens your dog, it’s likely to frighten your cat, too.

Suggested Solutions for Pica

Pica can be a serious problem because items such as rubber bands, socks, rocks, and string can severely damage or block an animal’s intestines. In some instances, the items must be surgically removed. Because pica can be potentially lifethreatening, consult both your veterinarian and an animal behavior professional for help. Here are some other suggestions.

• Make the objects your pet is eating taste unpleasant by applying cayenne pepper, Bitter Apple®, or some other aversive. (For more information on using aversives, see “Using Aversives to Modify Your Cat’s Behavior” and “Using Aversives to Modify Your Dog’s Behavior.”)
• Prevent your pet’s access to these items.
• If your pet is highly food-oriented, change her diet to a low-calorie or high-fiber diet. This may allow her to eat more food, more often, which may decrease the behavior. Check with your veterinarian before changing your pet’s diet.
• If you suspect that anxiety or frustration is the reason for your animal’s pica habit, change the behavior by using behavior modification techniques.
• If you catch your pet ingesting items and believe it is to get attention, startle your pet with a loud noise or a spray of water. If possible, avoid letting her know that the startling noise or spray comes from you, and be sure to praise her when she leaves the items alone. You may want to give her something acceptable to eat or chew. Try to set aside 10–15 minutes twice a day to spend with your pet so that she doesn’t need to resort to pica to get your attention.
• If you think your pet’s pica habit is play behavior, then keep plenty of toys around for her to play with. Cats especially like to play with string, rubber bands, and tinsel, and ultimately ingest them. Keep these items out of reach and provide a selection of ppropriate toys. (See “Cat Toys and How to Use Them” and “Dog Toys and How to Use Them.”)

What Doesn't Work

• Interactive punishment (punishment that comes directly from you, such as verbal scolding) is usually not effective because it may be interpreted by your pet as attention. What’s more, many animals learn to refrain from the problem behavior when their owner is present, yet still engage in the behavior when their owner is absent.
• Punishment after the fact is never helpful. Animals don’t understand that they’re being punished for something they did hours or even minutes before. This approach won’t resolve the problem and is likely to produce either fearful or aggressive responses from your pet.

Adapted from material originally developed by applied animal behaviorists at the Dumb Friends League, Denver, Colorado.

©2000 Dumb Friends League and ©2003 The HSUS. All rights reserved.