Tongue Fu: Why Do Dogs & Cats Chew, Suck On, And Eat Strange Things?

Pica (pronounced “PIE-kuh”) is the behavior of eating nonfood materials.

The most common form of pica in cats is wool sucking. The most common form of pica in dogs is coprophagia. In this post I’ll describe strategies for managing the behavior or putting an end to it, as well as theories about some of the causes of pica.

Jump to:
Is pica dangerous | What causes pica | Wool sucking (Cats) | Environmental approaches to managing wool sucking | Behavioral approaches for managing wool sucking | Additional approaches to consider | Pharmaceutical options for managing wool sucking | Coprophagia (Dogs) | Behavioral causes and solutions of coprophagia | Nutritional causes and solutions of coprophagia | Pharmaceutical options for managing coprophagia | Select sources

 

Is pica dangerous?

Pica in and of itself isn’t a problem as long as the objects of affection are safe for the animal to chew or suck on. For example, some cats seem attracted to plastic bags, which obviously pose a suffocation and choking hazard if any pieces of plastic are swallowed or breathed in. Other risks are that the targeted objects can be permanently damaged, and human-animal relationships can suffer if the behavior bothers people living with the animal who has pica.

There are certainly hazards if any nonfood material is swallowed, of course.

 

What causes pica?

Pica is one of those lingering mysteries – scientists have not yet figured out what causes it. The most common theories are:

• Stress and anxiety
• Boredom
• Premature weaning
• Underlying medical condition(s)

If medical conditions are causing pica, the behavior will continue until the medical condition is identified and treated. So to put an end to this behavior, the dog or cat must receive a thorough veterinary exam. Some of the health issues that have been associated with pica are:

• Anemia
• Diabetes
• Liver disease
• Thyroid disease
• Skin diseases
• Pancreatic disease
• Nutrient deficiencies
• Central nervous system diseases
• Chronic pain
• Hypersensitive skin
• Intestinal parasites
• External parasites (like fleas)
• Bowel diseases affecting the intestines
• Senility

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Wool sucking (Cats)

Wool sucking is the most common form of pica in cats. This condition is often called “wool sucking” because many cats suckle on the fabric like kittens suckling on their mothers. The most frequently favored objects are fabric, cardboard, plastic bags, rubber bands, electrical cords, hair, earlobes, and leather.

Other compulsions that frequently accompany pica in cats are extreme licking or grooming, excessive chewing of the skin, persistent pacing, and repetitive meowing (vocalizing).

The majority of cats with this behavior are Oriental breeds (Siamese, Burmese, Balkinese etc.) or their crosses (Bombay, Oricat, etc), which leads many scientists to believe there is a genetic basis for the behavior.

Behavioral approaches for managing wool sucking

Punishing cats for compulsive behavior (like pica, if it is a compulsion) increases their stress, leads to additional fear and aggression, and actually worsens the behavior.

One of the most effective approaches to managing wool sucking is moving their objects of desire out of reach. If this is impossible, consider applying an unpleasant tasting substance to the items. Products like Bitter Apple are designed for this purpose and there are also a number of homemade deterrent solutions. If possible, sprinkle black pepper on the item of affection. If it’s difficult to sprinkle pepper on it, make a liquid pepper solution to spritz on the item: dissolve black pepper in hot water, put the pepper-water in a spray bottle, and spray pepper-water on the object. Citrus scents have similar effects on cats as pepper.

Behavior modification programs such as clicker training can be very successful. These programs usually consist of ignoring the unwanted behavior and rewarding wanted behavior as much as possible – including times when the cat is doing nothing. These programs also usually include diverting their attention with toys or interactive play when cats are caught in the act.

Another very successful tactic is to provide one or two objects that are ok to suck or chew on. This enables cats to express pica in a way that is easier to live with. This is especially useful when combined with giving unpleasant tastes to other materials, as described above.

Environmental approaches to managing wool sucking

If a cat’s pica is a reaction to stress and anxiety, using general stress-reducing strategies is a recommended tactic for pica, too. A few of the easiest are:

• Provide enough quiet nesting places for each cat to call her own, especially places that are elevated where she can exert her dominance. Shelves in closets are an excellent choice, for example.
• Playing soothing music can help cancel out startling or upsetting noises. I do this when there are fireworks going off in my neighborhood.
• Eliminate unpredictable events as much as possible. For example, set regular, predictable times for feeding, cleaning litter boxes, and interactive playtime.
• Pheromone (pronounced “FAIR-oh-moan”) sprays and diffusers (such as Feliway) are worth a try. I’ve seen these help a significant number of animals, including my own.
• Rescue Remedy or other calming flower essences are also good options. They have done wonders for my own cats. (I use custom blends, designed just for my cats. They’re more effective and cheaper than over-the-counter flower essences. My flower essence lady is Lin Gregerson, 360-229-0389, jlgregel@hctc.com)

If cats are bored, enhancing their environments can help channel unwanted behaviors. The most effective approaches to environmental enrichment for cats are:

• Provide plenty of perches (especially near windows).
• Purchase interactive toys AND USE them. (Wink, wink.) I know, we all have good intentions when we buy interactive toys but we lead such busy lives that finding time to play with our cats is… Well… Sometimes… You know…
• Supply scratchers. Posts made out of real wood are awesome and easy to find these days. For years my cats used one piece of firewood. Now they have perches made of driftwood, and Scratch Loungers.
• Rotate available toys. Offer a few toys at a time, hide the rest, and rotate the available selection every few days. I store toys in a container with catnip so when I get toys out, they’re even more appealing. Also, try experimenting with old toys in different situations: inside paper bags, boxes, or cardboard tubes from paper towel rolls. Different types of boxes offer completely different experiences: experiment with small cereal boxes, larger cardboard boxes, and produce boxes with holes in them. Introducing the same old toys but in different situations is the best way to extend the life of a cat’s toys.
• Create opportunities for cats to climb, explore their territory, and hide in different areas. Cats can be enticed to explore and hunt by placing treats or toys (especially those that smell like catnip) in a variety of places: under furniture, on perches, in windowsills, and in boxes or bags. Every day can provide a new experience if the hiding places change regularly. Hunting treats and kibble hidden around the house is one of my cats’ favorite activities.
• Offer indoor cats opportunities to watch outdoor activities. For example, place bird-feeders/baths within view from a cat’s favorite window.

Pharmaceutical options for managing wool sucking

Some cats respond well to prescription medications that curb compulsive behavior, such as fluoxetine (Prozac), clomiprimine, and amitriptyline. A veterinarian can provide more information about medicines that might be helpful for an individual cat.

Additional approaches to consider

• If a cat is wool sucking in order to supplementing her diet with more roughage, try increasing the amount of fiber in her diet. This can be done by feeding hairball formula foods or by adding pumpkin or squash to her diet. (Not all wool sucking is due to a dietary need.)
• Acupuncture and massage can be very helpful. Marnie Black, an animal massage therapist who works at Hawks Prairie Vet, can teach you massage techniques to use at home.

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Coprophagia (Dogs)

Coprophagia, or eating feces, is the most common form of pica seen in dogs.

An adult dog in a stable environment that suddenly begins to engage in coprophagia should be seen by a veterinarian as soon as possible. It could be an indication that there is a new digestive issue.

Using a litter box as an all-you-can-eat buffet is probably the most common expression of coprophagia. The ideal way to begin to change the behavior is to remove the buffet: move the litter box to an area the dog doesn’t have access to. (It might help to use magnetic locking doors to keep dogs out of the litter box area. If you want more info about these, lemme know. I’ve used ‘em for years.)

Behavioral causes and solutions of coprophagia

Some people believe that coprophagia is behaviorally motivated. They point out that dog owners often create a situation in which the behavior is inadvertently reinforced. That’s because most people give a dog attention immediately after the dog has scarfed down some poo. Doing this can condition dogs to continue the behavior because it triggers the start of some very animated human attention. Things get so EXCITING when they eat a little poop!

This is why the most commonly used approach to ending the fecal feast is to simply ignore the behavior. Coprophagia often begins when dogs are just young puppies and it usually fades away as puppies get older if it is not reinforced. When puppies do something that makes their humans get really excited they think they’ve discovered an opportunity to play. If they get no reaction from their humans, the puppies don’t associate eating poo with a fun response from the people around them.

Some theories of why dogs eat poo carry more weight in families with owners who pick up feces immediately after the dog has eliminated. The theory is that dogs might be motivated to mimic their people: after a dog poops, we clean up the poop. Again, not making too much of the behavior is a good tactic to start with.

Coprophagia is sometimes a two-dog problem. Theories about this suggest that some dogs eat the feces of another dog as a way to express dominance and negotiate social power. If this is the reason that a dog eats poo, it’s best to try to address social issues as a whole if possible, instead of focusing just on the poop-grazing.

As with cats, it can help to apply an unpleasant tasting substance to the items. Using products like Bitter Apple or a homemade deterrent solutions (like the pepper described above) can sometimes help.

Behavior modification programs such as clicker training can be very successful. These programs usually consist of ignoring the unwanted behavior and rewarding wanted behavior as much as possible – including times when the dog is doing nothing. These programs also usually include diverting a dog’s attention with toys or interactive play when they’re are caught in the act.

Another very successful tactic is to provide one or two objects that are ok to suck or chew on. This enables dogs to express pica in a way that is easier to live with. (This is especially useful when combined with giving unpleasant tastes to other materials, as described above.) This worked with my client, Daisy, when we gave her a little lamb (from Sherpa GoDog’s Flats line of plush, unstuffed toys – they also make a line called Furry Flatties) that she decided to use instead of her former favorite object of oral fixation: a rug. See the photos.

Nutritional causes and solutions of coprophagia

Some dogs may have actually a true nutritional reason for engaging in coprophagia. The Merck Veterinary Manual says that “it is very difficult, although not impossible, to rule out all physiologic causal associations.” Nutritional reasons for coprophagia are often linked to some kind of digestive inadequacy. For example, enzyme deficiencies or congenital digestive abnormalities, can lead to inadequate digestion, malnutrition, and a dog feeling the need to digest foods more than once.

When this is the case, the poo eating can often be stopped by adding a digestive enzyme, probiotic, or prebiotic supplement to a dog’s food. Optagest is my prebiotic supplement of choice, but there are tons of ‘em on the market.

Pharmaceutical options for managing coprophagia

Another approach to curbing coprophagia is to make the poo less tasty. Most people use a capsule or tablet that contains capsicum (the compound in peppers that makes them hot), such as Stool Repel-um. When the tablets hit the intestines, the capsicum is released making waste taste very hot – unpleasant for most dogs.

This works especially well when combined with the behavioral solutions described above.

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Select sources

• Case, Linda. The Cat: Its Behavior, Nutrition and Health. Ames, IA: Iowa State Press, 2003.
• Case, Linda. The Dog: Its Behavior Nutrition and Health. Ames, IA: Iowa State Press, 2005.
• Christensen, Wendy. Outwitting Cats: Tips, Tricks, and Techniques for Persuading the Felines in Your Life That What You Want is Also What They Want. Guilford, CT: Lyons Press, 2004.
• Aiello, Susan, ed. Merck Veterinary Manual. Whitehouse Station, NJ: Merck, 1998.
• Schelling, Christianne. “Pica in Cats: Why Cats Eat Strange Things.” CatHealth.com. 4 Oct 2011. http://www.cathealth.com/how-and-why/pica-in-cats-why-cats-eat-strange-things
• Shojai, Amy. New Choices in Natural Healing for Dogs and Cats. New York: Rodale, 1999.
• Sueda, Karen. “Pica: The Un-Finicky Feline.” Best Friends Animal Society. 4 Oct 2011. http://www.bestfriends.org/theanimals/pdfs/cats/catpica.pdf