Photo by Alvan Nee
Fleas are the most common external parasite of pets in North America. Fleas are small wingless insects that use their specialized mouth to pierce the skin and siphon blood from their host. When a flea bites, it injects a small amount of saliva into the skin to prevent the blood from coagulating. Some animals become sensitized to flea saliva and animals that are allergic can have severe itching and scratching from a single bite. Flea allergy dermatitis is the most common disease among dogs.
Current flea control products are primarily either oral or topical systemic treatments. Most of the products may be used for prevention as well as to treat existing flea problems. One group of products control fleas by interrupting their development by killing or stopping the maturation of flea larvae and eggs. These drugs are called Insect Growth Regulators (IGRs). One common oral product used is lufenuron which is found in the Program® line of products which are administered orally in tablet or liquid form. Methoprene and pyriproxifen are also IGRs that are available as sprays or collars. The FDA shares regulation of these products with the Environmental Protection Agency and the U.S. Department of Agriculture. Because even the same products from other countries have not been approved by these agencies, it is illegal to purchase or import these products for use in the United States.
Currently the most popular flea control products kill adult fleas (adulticide), are applied topically and work rapidly. Popular topical products utilize fipronil which is the key ingredient in Frontline® Top Spot and imidacloprid which is in Advantage®. The most popular product on the market, Frontline Plus®, utilizes both an adulticide and an IGR. An oral adulticide that is also available is nitenpyram which is in Capstar® and begins to kill fleas in 30 minutes. Frontline Plus also kills ticks which makes it the most popular product where ongoing tick protection is required.
Consult with your veterinarian to determine which flea and tick control products are best for you. The choice of flea control will depend on your climate, environment, your pet's activities, and potential for exposure. However, with consistent use, it is almost always possible to control your flea problem. Using these products throughout the year typically will eliminate the need for regular insecticidal use. The following provide additional summary information on selected popular products.
Program from Novartis®
Program is available as a once a month pill or oral liquid suspension to be given with a full meal. Adult fleas that ingest Program's key ingredient, lufenuron, produce sterile eggs. Program does not kill adult fleas so pets remain susceptible to fleas hatching and maturing pupa already present in the environment. Therefore, some time may pass before the all fleas are killed in an environment. In order to stop the life cycle, every animal in the environment must receive lufenuron. Pets should also be sprayed with an adulticide during the first week or two of starting Program.
Advantage from Bayer®
Advantage is applied topically on both dogs and cats and seems to be very well-tolerated by sensitive cats. Advantage kills fleas within 24 hours and 100% protection can be maintained for cats for 21 days and 90% protection can be maintained for dogs for 28 days. Advantage is susceptible to washing off so dogs that are active outdoors and dogs that swim or must be bathed frequently should be re-treated frequently. Up to weekly re-treatment is allowed. The imidacloprid in Advantage does not effect ticks, but K-9Advantix, with permethrin does. K9 Advantix is only labeled for once a month K9 Advantix is ONLY FOR USE WITH DOGS and MUST NOT BE ADMINISTERED TO CATS.
Frontline Spray, Frontline Plus And Frontline Top Spot from Merial®
Frontline Spray, Frontline Plus, and Frontline Top Spot comprise the market leading Frontline flea control product line. The fipronil in Frontline products is a broad spectrum insecticide available as a spray or topical. Fipronil works by binding chemically to the pet's hair and is absorbed through the follicle by the sebaceous glands. As a spray, fipronil kills fleas at 95% for over 80 days after application on dogs and for 1 month with biweekly bathing. Frontline is labeled for puppies and kittens as young as 8 weeks (10 weeks for Top Spot) and it is not washed off by bathing. Frontline is also affective against ticks. Some cats may show minor adverse reactions with high volume use of the alcohol based spray product which should be applied no more than once a month. Frontline Plus also contains the IGR, S-methoprene which inhibits the growth of immature fleas.
Capstar from Novartis®
Capstar is an oral tablet for dogs and cats that may be administered as young as 4 weeks of age. It offers extremely rapid and complete killing of adult fleas and is safe enough that the tablets may be used whenever fleas are seen on your pet as often as once per day. Capstar may be used in combination with an IGR to kill fleas immediately to compliment the long-term control of an IGR such as Program.