Virbac Effipro Spot On Flea Treatment for Cats is an effective treatment and prevention of fleas and ticks on cats. It is based on new a formula containing Fipronil, an insecticide and acaricide belonging to the phenylpyrazole family. It get to work on killing pests straight away, and will usually clear fleas within a day, and persistent ticks within 48 hours. Fipronil is a strong agent that provides fast action that lasts for up to 2 weeks. A one month interval is recommended between applications.Dosage: One 0.5mlpipette per cat, per treatment.WARNINGS Do not use on sick or recovering pets Do not use on rabbits, it could be fatal Do not use if your pet is allergic to any of the ingredients Do not get in eyes Do not allow the pet, or other pets to lick the treated area Keep treated pets separated from children until the application is dry