Originally published in the April 2015 issue of Veterinary Practice News
The most effective flea- and tick-control products are the ones that pet owners will actually use according to the label recommendations.
So believes Michael Murray, DVM, technical marketing director for U.S. Pet Parasiticides at Merial Ltd. of Duluth, Ga.
“While that may seem simple and obvious on the surface, many important factors influence the outcome,” said Dr. Murray said.
By probing into a pet’s routine with a few questions, veterinarians can ferret out those factors and help ensure compliance – leading to what is likely to be a better outcome for patients, Murray said.
“First, what is the pet owner’s perception of the value, not the cost, of using flea and tick control for their pet?” he said. “This differs among pet owners, and finding out how clients spend time with their pets can provide important insights into how a parasite infestation would affect the relationship between the owner and their pet.”
One question he suggested be posed to clients is whether a pet sleeps with a family member and how a flea or tick infestation would affect that interaction. He also suggested that veterinarians should find out if the pet owners take their dog to dog parks or other places where pets congregate.
“This not only provides insights into how they spend time with their pet, but also indicates an increased risk for exposure to fleas and ticks,” he said.
Veterinarians should find out what type of pest control the pet owner prefers. While oral products have grown in popularity, many pet owners still prefer to use topical products, Murray said.
“Ease of administration and palatability are important considerations for oral products,” he said.
Veterinarians may be able to do more than just instruct clients on how to use flea- and tick-control products. Many pet owners want their veterinarians to provide information on which products to use, as well as information on safety, the parasites a product can control, ease of administration and options among oral or topical products.
“We also know that most pet owners who go to the veterinarian prefer to purchase products from the clinic, which means that having these conversations with pet owners can lead to agreement for using flea and tick control on their pets,” Murray said.
You’ll get no argument there from Michael W. Dryden, DVM, Ph.D., Dipl. ACVIM, university distinguished professor of diagnostic medicine and pathobiology at Kansas State University.
Dr. Dryden, too, believes the most effective flea products on the market are the ones that are actually used.
“Sounds simple, but most people start too late,” said Dryden, who is also known as Dr. Flea.
He advised veterinarians to remind clients that it only takes a female flea 24 hours to begin laying eggs, and at 40 to 50 eggs per day, it does not take long for a massive infestation to occur.
“Also, typically by the time you see a tick, it can be too late to prevent disease transmission,” he said. “There are a number of really good flea and tick products today, but they do not work sitting in a tube in a box.”
An informative conversation that should be had with clients is one that dissuades them from the belief that flea and tick control is seasonal, said Rusty Muse, DVM, Dipl. ACVD, owner of the Animal Dermatology Clinic in Tustin, Calif.
Muse said that while flea and tick control have come a long way, myriad misunderstandings and myths still surround the topic of fleas, Dr. Muse said.
“One of the biggest misunderstandings is that some owners use flea control only in the warm months,” Muse said. “However, in temperate climates like Southern California, flea control, especially in the allergic patient, is critical year-round. Fleas do quite well throughout the year in many locations around the U.S.”
Muse sees many pet owners who demand evidence of fleas before they institute control measures.
“Once there is a flea burden that is sufficient to make visualization by the owner easy, the horse is out of the barn and there is likely a significant flea population with various life stages of fleas present in the environment,” he said.
“It is easier to prevent flea infestation than to resolve it.”
Lance Hemsarth, an entomologist and senior director of research and development for The Hartz Mountain Corp., is a big fan of both topicals and oral pest control products.
“The most effective preventive treatments today are topical products that contain effective, fast acting adulticides combined with insect growth regulators for effective infestation control,” Hemsarth said. “Products that can repel parasites offer the best protection as parasites are prevented from taking a blood meal and transmitting disease.”
Oral flea and tick treatments are also a good option for some pet owners, Hemsarth said.
Muse noted that there are many oral and spot-on products on the market, and while they contain a variety of active ingredients, they all have benefit in allergic and non-allergic patients.
“Onset of action, residual effects and taking into account the patient and its environment are all important factors in choosing which of these products are the best choice for individual patients,” Muse said.
“For example, in many of our dermatology patients that require routine – weekly or more – bathing, I choose an oral product that would not be affected by topical therapy. For patients with no requirement for routine grooming or bathing, either topical or oral therapy would be reasonable.”
Dryden said veterinary-prescribed flea and tick products today are excellent, offering a few thoughts on some specific brands.
“While Frontline and Advantage have been long-standing excellent products, newer topical and systemic products like Activyl, Vectra, Comfortis, Nexgard and Bravecto are also excellent,” he said.
Dryden also considers oral systemic products to be highly effective.
“The key is not whether a product is a topical or oral, the key is the product’s residual activity or residual speed of kill,” he said, referring to the ability to kill newly acquired fleas and ticks days or weeks after application.
“If you can kill them fast enough, you can prevent flea reproduction, manage Flea allergy dermatitis and hopefully dramatically reduce the transmission of an infectious agent. So we no longer focus on topical or oral, we focus on residual speed of kill. Clearly these newer orals do this very well.”
While “all-natural” may be work to attract the attention of customers, some experts aren’t high on products that pitch a natural approach to flea and tick control.
Muse argued that the term “natural” often has different meanings to different people, but when referring to things like garlic and other types of supplements for flea and tick control, Muse’s yes-or-no take on whether these natural products work effectively is a definitive “No.”
“Studies that have critically assessed the effectiveness of these ingredients have consistently found them to be of no value,” he said. “Reports of benefits of these products are limited to anecdotal reports.”
Dryden agreed, and added a word of caution against considering them.
“There is no data to indicate natural products provide any benefit,” he said. “Therefore, using them can be harmful, since animals are getting exposed to blood-sucking and disease-carrying fleas and ticks.”
But Hartz’s Hemsarth said not all the natural products out there are ineffective.
“There have been effective natural products available for many years,” Hemsarth said. “Those which are formulated to achieve control the same as traditional pesticides can and do provide effective parasite control. An example would be the use of natural pyrethrins, extracted from chrysanthemums.”
Hemsarth did acknowledge that some natural products aren’t all they’re made out to be.
“Unfortunately, there are some natural products that do not work at a level to provide effective protection for humans and pets,” he said.
He noted that many natural ingredients designated by the U.S. Food and Drug Administration as “Generally Recognized As Safe (GRAS)” also also exhibit some degree of pesticidal activity.
“Examples are essential oils extracted from fruits and foliage,” Hemsarth said. “These ingredients are exempt from complying with conservative federal testing requirements. Without government agency oversight, products that contain only these GRAS ingredients are claiming effectiveness. In reality, they only provide limited effectiveness against parasites.”
That wouldn’t be a problem if a pet owner were dealing with relatively harmless household pests, but it is a problem for pests that present public health risks like fleas, ticks and mosquitoes, Hemsarth said.
“Disease transmission is the greatest threat,” he said. “High levels of performance are required for protection from these biting parasites. Only parasiticides which have been clinically tested and have successfully been reviewed and approved by the Environmental Protection Agency or FDA can provide pet owners with the assurance of performance and protection.”
Flea and Tick Product Safety
Safety issues with flea and tick products are uncommon and shouldn’t dissuade veterinarians from encouraging their clients to use them, experts say.
Muse said with confidence that safety concerns for topical and oral flea therapies is minimal.
“Of course, as with any medications that are used in humans and animals, individual animals may have a sensitivity to flea products both oral and topical,” Dr. Muse said. “Topical contact reactions can and do occur, but these are idiosyncratic type reactions and are quite uncommon in nature.”
The most common side-effect he sees with oral monthly products is gastrointestinal upset with vomiting, and while other reactions do occur in some patients, he said these are uncommon.
“The key question, as is the case whenever any medications are used, is, ‘Are the potential benefits to the patient higher than the possible risks and with flea control products?’ That answer is invariably ‘Yes,’” Muse said.
Hemsarth believes there are few safety concerns with oral products.
"When used as directed, topical and oral flea and tick products are well-tolerated by pets,” Hemsarth said. “Sensitivities can occur with any flea and tick product, but these reactions are usually mild and self-limiting.”
As with any product, safety is always and should always be a concern, said Dryden.
“However, after saying that, current FDA, EPA and industry safety standards are excellent and as long as labels are followed there really should be no concerns,” said Dr. Dryden, the university distinguished professor of diagnostic medicine and pathobiology at Kansas State University.
“Can rare reactions occur? Certainly. There are over 100 million pet dogs and cats in the U.S. Rare idiosyncratic reactions may and do occur.”