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Study Raises Concerns about ‘Natural’ Flea Products


Pet Column for the week of November 2, 2012


Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
Sarah Netherton
Information Specialist

Fleas are a year-round problem for pets. Flea bites cause mild to severe itching and skin infections in cats and dogs because of allergic reactions to the saliva of the flea. Fleas and their eggs survive and thrive in grasses, soil, carpets, bedding, crevices in flooring, and numerous other hiding places.

Naturally, pet owners are eager to find safe and effective products to get rid of fleas, or to keep them away in the first place. But according to a retrospective study published in the Journal of Veterinary Emergency and Critical Care in August 2012, owners would be wise to steer clear of products marketed as “all natural” if those products are not regulated.

The study, conducted by veterinarians at the University of Illinois College of Veterinary Medicine and at the ASPCA Animal Poison Control Center in Urbana, examined natural flea products, whose active ingredients were essential oils extracted from plants and thus were exempt from Environmental Protection Agency (EPA) regulations. Records from the poison center relating to 39 cats and 9 dogs that had been exposed to natural flea preventatives were evaluated for this study.

Even when the natural flea products were used as directed on the packaging, 92% of the animals in the study were found to have at least one adverse effect after being exposed. The effects of the plant-derived oil observed in both cats and dogs included agitation, hypersalivation, lethargy, vomiting, panting, weakness, and seizures. Cats were more likely to exhibit adverse side effects.

“Cats are more frequently adversely affected by topical flea preventatives than dogs are because their grooming and licking behavior leads them to ingest more of the product,” says Dr. Tina Wismer, a veterinarian at the ASPCA Animal Poison Control Center and an adjunct instructor at the University of Illinois.

According to Dr. Wismer, more than one in ten calls to the poison control center in 2011—or over 18,000 unique cases—related to insecticides. Of these, nearly 11,000 concerned flea and tick products.

Callers to the Animal Poison Control Center have reported a variety of adverse effects in their pets related to use of a natural flea product.

“Sometimes it can be as minor as a little drooling,” explains Dr. Wismer, “while other times an animal may be having a seizure due to the product. There is just such a wide range of side effects when using something that is not regulated by the EPA.”

The purpose of the recent study of the “natural” flea product was to highlight the need for EPA regulation, since these products were shown to cause many adverse, and sometimes severe, side effects in a majority of the subjects.

While the researchers in the study recognize that essential oils may have therapeutic benefits, they are concerned that how these compounds work is not yet clearly understood.

“Just because something claims to be ‘all natural’ does not mean that it is safe,” says Dr. Wismer. “Your local veterinarian can recommend a safe and effective flea treatment or preventative for your dog or cat.”

For more information about flea products, speak with your local veterinarian.