The Animal Doctor

Clay Litter Causing Digestive Issues

DEAR DR. FOX: We just adopted another kitty from a nearby humane society. She is 8 years old and had been at the shelter for four months after being turned in with another 11 cats.

Dolly had diarrhea with blood, and was throwing up her food almost every time she ate. We feed her only grain-free wet food. After four weeks, she had a bowel movement and produced a hard, finger-length, gray piece of stool, which was like clay. She repeated another stool with the same substance a few days later.

Dolly is a very clean cat, and licks herself after eating and using the litter box. We’ve been using a corn-based litter for many years with all our cats, but at the shelter, they used a clay-type litter.

Since expelling this substance, she has not thrown up again and has no blood in her stool. She also had trouble with her eyes, which were full of debris from the old litter. We have told this to our vet and the shelter; neither seems to know about something like this.

Our hope is that, if this was caused by the gray claylike litter, that people will read this and think twice about using it. -- M.K. and D.K., Kansas City, Missouri

DEAR M.K and D.K.: Your letter is important for all cat owners and veterinarians not yet fully aware of the risk of some kinds of cat litters to cats’ health.

Cats with long fur, coupled with a clay-type litter material that clings to their fur, are especially at risk. As they groom themselves, cats pull out some loose fur -- and anything clinging to it -- with the lingual comb of backward-directed rasps on their tongues. They then swallow some of that material. This includes household dust, which is probably more toxic than clay, but of an insufficient amount to cause an intestinal obstruction like clay litter evidently does.

I, too, have used and recommend corn-based cat litter, with the warning that there will likely be some residual glyphosate herbicide -- a probable carcinogen.

DEAR DR. FOX: My dog Louie has allergies. He licks his paws till they’re red or bleeding.

He is on Benadryl and Apoquel from the vet, but nothing is helping. He also has dry eyes, which cause a thick substance over his eyes. Is there something simpler to deal with this allergy situation? -- L.I., St. Louis, Missouri

DEAR L.I.: Your dog and many others are suffering terribly, most probably from multiple chemical sensitivities at the root of this kind of immunological pathology.

Stop the Benadryl, which can cause dry eyes and other problems. Prednisolone can help bring relief and stability, but that is generally temporary if the allergens/triggers that disrupt the immune system are not removed from the patient’s environments. It can be difficult to identify them, in part because there are thousands to consider in the air, food, water, household dust and outdoor lawns and gardens. Various tests may identify specific allergens, but there can be cross-allergenicity and sensitivity to other similar compounds not covered in the allergy test.

Regardless, we must embrace the precautionary principle with regard to chemicals in our shared environments and get rid of most nonessential cleaners and disinfectants. Instead, use natural, biodegradable ones where possible (like vinegar and baking soda), and avoid all synthetic fragrances in products in the home. Avoid pesticides -- in and around the home, but also their topical and oral application to cats and dogs (such as year-round anti-flea pesticides).

Of course, an additive-free, Certified Organic ingredient-rich pet food may also help your dog, as per my recipe on my website, I would use a different animal protein in weekly rotation and see which suits him best. To help reduce possible contact allergies, have him lie on clean cotton sheets, washed with unscented laundry detergent.


A Denver City Council panel advanced a proposal to ban cat declawing, except when medically necessary, over the objections of the Colorado Veterinary Medical Association (CVMA).

“We support the principle that complex medical decisions belong in the domain of the owner and the veterinarian,” said CVMA President Dr. Will French. (Denver Post, Oct. 25)

In my opinion, the CVMA should move into the 21st century and consider veterinary bioethics when addressing “complex medical decisions.” This is the essential heart of veterinary practice, beyond running a business, as per my previous writings. The routine declawing of cats is outlawed in most other civilized countries.

(Send all mail to or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

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