Three weeks ago, in response to an increase in adverse reactions to spot-on flea and tick products, the U.S. Environmental Protection Agency (EPA) announced that some smaller dogs tend to disproportionately suffer with adverse reactions due to over-dosing and misuse, and that it had launched an investigation into how products could be more clearly labeled to avoid misuse. Now, the Pet Poison Helpline has concurred that the incidence of severe and fatal effects resulting from the application of flea and tick products is extremely low as compared to the number of applications that pet owners apply each year, and that when serious events occur, it is most commonly a result of misuse. For example, when dog products are applied to cats or when owners misread, misuse or miscalculate the dose or product that is appropriate for their animal.
The help line warned that treatment with a fast-acting topical flea and tick medication can cause itching or brief irritation and fidgeting at the application site, which can be alarming to pet owners. A small proportion of treated animals can also develop a side-effect called paresthesia, a tingling sensation around the application site. While this is normally a very localized and short-lived side-effect, it accounts for a large number of the few incidents reported to the help line. In fact, based on sales and distribution data individually presented to the EPA by various companies, the overall incident rate for flea and tick products was calculated to be approximately 16 incidents per 100,000 applications. And the overall incident rate for cases classified with either a major or fatal outcome was about one in 200,000 applications.
"These data demonstrate that Spot-On products are generally safe when used appropriately and according to the directions," said Dr. Lynn Hovda, DVM, DACVIM, director of veterinary services for Pet Poison Helpline.
The Pet Poison Helpline says that the key to ensuring your pet’s safety when using flea and tick products is to select a product specifically for use on your kind of pet – for example always choose a cat product for use on cats – and to be vigilant about following the instructions on the package. Knowing the exact size and weight of your pet is essential for using the correct medication and appropriate dose on your pet. It is also recommended that you consult a veterinarian before using flea and tick products on weak, aged, sick, pregnant or nursing pets.