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Animal Doctor: Chemical additives in pet foods can cause seizures

Animal Doctor: Chemical additives in pet foods can cause seizures

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Dear Dr. Fox: My 8-pound Maltese is 12 years old and had his first seizure this week. And then today he had another one. I read your article that melatonin will benefit a dog with seizures. Is this true about melatonin, and what daily dosage do you recommend?

I took him to the vet and they took a blood sample and did chest X-rays. The vet said everything looked good. If the seizures happen again, the vet informed me she would put him on anti-seizure barbiturate medication. — R.R., Albuquerque, New Mexico

Dear R.R.: There are many reasons why dogs have seizures. But I would recommend giving 3 mg melatonin before bedtime and a teaspoon of coconut oil in every meal.

Good luck. More tests may be needed. I hope his recent vaccination history or flea treatment has not caused the seizures.

R.R. replies: Thank you for your reply. The melatonin stopped my dog’s seizures. While doing some research online, I discovered that rosemary extract and a dye called red 40 can cause seizures in small dogs. Two of his treats had these ingredients. Since removing these treats from his diet, his seizures have stopped.

Dear R.R.: I commend you for your research. I did a quick internet search and found this discussion from 2006:

I also covered this in a 2009 column:

Dear Dr. Fox: As you have written before, red dye 40 may cause seizures in dogs. I have found that it does so in my 12-year-old Aussie mix, Petey. In addition, I have found that Petey will have a seizure when I give him a bit of cheddar cheese that includes the additive annatto. I now read every label carefully to be sure that neither of these ingredients is included in anything that Petey might ingest. — F.C., East Lyme, Connecticut

Dear F.C.: Annato has been linked with many cases of food-related allergies and is the only natural food coloring known to cause as many or more reactions than artificial food coloring. Because it is a natural colorant (from the seed-pulp of a tropical tree, the Achiote, or lipstick, tree), companies may label their products “all natural, no artificial colors,” and this can lend a false sense of security to consumers who suffer from dye allergies.

Cat and dog food manufacturers should cease and desist putting red 40, a petrochemical azo dye, in their products, including treats. Nestle Purina uses red iron oxide instead. Why? It’s only for us! Cats and dogs are red-green colorblind, but we humans may think it is some kind of meat. “Natural flavoring,” meanwhile, could mean monosodium glutamate (MSG), which can also cause seizures.

Rosemary extract is used as a preservative, and its use should be reconsidered since it too can cause seizures as you have experienced.

In an earlier column I shared the story of a cat who developed seizures from being given a popular brand of cat treats and became so conditioned that she would have a seizure upon hearing the bag of treats being opened!

My advice is to avoid manufactured and colorful kibble and treats and look for organically certified, frozen, freeze-dried or preservative-free canned foods. Try a variety of brands and different protein ingredients; variety is the spice of life and is one way of avoiding deficiencies or excesses.

Investigation into Canine Dilated Cardiomyopathy (DCM) continues: The FDA continues to investigate possible links between boutique dog foods, including grain-free products, and canine dilated cardiomyopathy. Some research has implicated pulses like lentils and peas, which have been used for years in dog foods but appear in greater quantities in grain-free products, says FDA spokesperson Monique Richards. Veterinary cardiologist Bruce Kornreich says the source of legumes might also be a factor, and Pet Food Institute CEO Dana Brooks says diet “may be among several elements involved such as individual dog physiology.”

Send all mail to or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.


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