Ingredients of Frontline Plus for Dogs

Fleas can cause tapeworms in your dogs.
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There are a variety of topical and internal products available to keep your dog free of fleas and ticks. Among the topicals are Frontline, Frontline Plus, Advantix, Advantage and Topspot. Some of the oral preparations include Capstar, Comfortis, Program and Revolution. These products work in similar ways to keep your dog free of fleas and ticks. The basic ingredients of the topicals is the same. The ingredients for Frontline Plus do more for your dog than the ingredients in Frontline. They are from the Merial family of pet products.

What Fipronil Is

Ticks are blood-sucking parasites that are members of the arachnid family. Images

According to the National Pesticide Information Center, the active ingredient in Frontline Plus, fipronil, is from a chemical called phenylpyrazole. Phenylpyrazole controls pests such as ants, beetles, roaches, fleas, ticks, termites and many other insects. It was patented in the United States in 1996.

Not Working?

Puppies can be put on Frontline Plus from the time they are 8 weeks old.
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In order for fipronil to work, the insect must have contact with it. That is why many pet owners will complain to their veterinarian that they still see fleas or ticks after application of Frontline Plus. According to Dr. Lorraine Kassarjian, a South Florida veterinarian who knows all too well about year-round flea and tick infestations in her clients, "The tick or flea must have contact with the product to get the insecticide into it, that's the only way it will die. People see ticks and fleas and think the product is not working. It is working, what they are seeing is dying ticks and fleas." The Frontline Plus website states that a tick may even attach itself, but will be dead within 48 hours.

Frontline Plus

Frontline Plus also contains a chemical called S-methoprene. This product prevents flea and tick larvae from developing into adult insects. So while fipronil kills fleas and ticks on contact, S-methoprene kills the eggs and larvae. This is how Frontline Plus continues to work for an entire month after application. The Enviromental Protection Agency states that S-methoprene does not have any "harmful effects on wildlife, humans, or the environment when used as specified on the product labels."

How It Works

When Frontline Plus is applied to your dog's body, it spreads all over the body via the oil gland system. It is replenished onto the skin and coat. It is waterproof and is effective for about a month. Frontline Plus recommends that pet owners use Frontline Plus once a month for maximum efficacy. The product is applied via a dropper on the vial to the dog's neck, where he cannot reach it with his tongue or paws. You should not pet your dog for 24 to 48 hours after application or you will get the product on your hands. Initially, you will see an oily spot appear on the area where you have applied the product, but that disappears within two days.