Frontline Spray provides long-lasting, effective control of fleas and ticks on your pet. It kills up to 100% of existing fleas in less than 24 hours. Frontline Spray continues killing fleas for an entire month or more. For: Cats and Dogs (8 weeks of age and older) Benefits: Effective against severe existing flea and tick infestations, and kills chewing lice Effective against all stages of ticks, including deer ticks (the major carrier of Lyme disease) Helps control sarcoptic mange infestations Remains waterproof for 30 days, even if your dog or cat swims or is bathed How it works: The active ingredient of Frontline Spray is fipronil, a broad-spectrum insecticide that disrupts the insects central nervous system. Cautions: Wear household latex gloves when using Frontline Spray. Consult a veterinarian before using on medicated animals, animals being treated with other pesticides, and debilitated, aged, pregnant, or nursing animals.