The big news on the flea and tick front is that the patent has expired on fipronil, one of the active ingredients in Frontline Plus, a leading brand, opening up the market to competitors. In May we found two that were new to the market, Sentry FiproGuard Plus at Petco and PetArmor Plus at Walmart. The savings can be sizable. PetArmor Plus was the best deal we saw: A three-month supply cost $28, compared with $50 for FiproGuard Plus and $62 for Frontline Plus at Petco.
When you choose a flea treatment, keep in mind the importance of killing not just adult fleas but also the eggs or larvae, suggests Mike Merchant, Ph.D., a professor and entomologist at the Texas AgriLife Research & Extension Service at Dallas. Insecticides containing S-methoprene, for example, cause fleas to lay sterile eggs and disrupt the larval flea's ability to develop properly. S-methoprene is found in Frontline Plus as well as FiproGuard Plus and PetArmor Plus.
Advantage II, a leading brand with different active ingredients, is also effective, Merchant says. In May we saw it selling for about $52 for a four-month supply at Petco.
We found other brands for as little as $9, but be careful. Some inexpensive products might not be as effective and might require you to spray or treat more often, Merchant notes. "The more insecticide you find yourself using, the greater the health and safety risks to you and your pet," he says.