Chemicals in Frontline for Animals

Frontline, one of the most popular products to control fleas and ticks in dogs and cats, contains a variety of chemical ingredients. These ingredients cause the death of the pests on the animals and repel them as well. Frontline contains two active ingredients, fipronil and methoprene, that make up about 20 percent of the product's composition. The rest is made with inert ingredients. Frontline can be effective if used properly and should only be placed on your pet with a veterinarian's consent.

  1. Fipronil

    • Fipronil is the chemical in Frontline that kills fleas and ticks. According to Dr. Sally Gardiner of the Pet Shed website, fipronil causes hyperstimulation of the flea's nervous system upon contact with the ingredient. This chemical essentially inhibits the nervous system of the pest. As a result, the flea's nerves will react excitedly, causing the insect to spasm and eventually die. The fipronil is mixed with an oil carrier to spread through the skin and collect in the hair follicles, states Dr. Holly Nash of the Pet Education website.

    Methoprene

    • Methoprene is an insect growth regulator, meaning that it prohibits the flea's growth. This chemical mimics the activity of the hormone that keeps fleas young. Upon contact with methoprene, the flea larvae never develop into adults and die. Keeping the fleas in the larval state prevents the opportunity for them to reproduce and create even more fleas. Methoprene also has ovicidal and embryocidal effects on female fleas.

    Carbitol

    • Carbitol is listed as an inert ingredient of Frontline, states the Vet Info website. This chemical, also called diethyline glycol monoethyl ether, is used to rapidly dry the animal's skin so that it better absorbs Frontline. Although experiencing an overdose from this chemical is rare, it can occur. Signs of an overdose include coma and suppression of the nervous system. If your animal is experiencing such issues, contact your veterinarian immediately.