Long-lasting, fast acting flea and tick control. Frontline contains fipronil, a flea adulticide. Fipronil works by affecting the parasite's (the flea's or tick's) nervous system causing paralysis and death of the parasite. Fipronil spreads over the pet's body with the body oils killing 98-100% of the fleas or ticks within 24-48 hours, and controlling transmission of tick-borne disease, such as Lyme disease.

Fipronil collects in the oils of the skin and hair follicles and then is released over time (up to 1 month) from the hair follicles onto the skin and hair. www.petmedstore.com

Frontline stays on even with bathing, swimming, or exposure to sunlight. Approved for use on puppies 8 weeks of age and older.