Major Uses

Fipronil and cyphenothrin is a combination of drugs that is commonly used to prevent and kill ticks, fleas, and chewing lice on dogs. It is also effective at controlling mites that can cause sarcoptic mange.

Common Precautions

Fipronil and cyphenothrin should not be used on puppies that are less than 12 weeks of age. It should never be used on cats, as it may be fatal if ingested. Animals should be watched carefully after application, as some animals may react negatively to pesticides. Should any unusual symptoms occur, a veterinarian should be contacted immediately before moving forward with treatment.

The most common possible side effect associated with fipronil and cyphenothrin is irritation at the site of application.

Fipronil and cyphenothrin should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if an overdose or any unusual symptoms occur.


Fipronil and cyphenothrin should be kept at room temperature and stored in a light resistant, childproof container. It should be kept in a location that is dry and protected from light, as well as out of reach from children and pets. It should not be refrigerated.


Fipronil and cyphenothrin is supplied as a topical solution that should be administered directly to the skin of the animal. It comes in individual packets that equal one dose each. It should be administered directly to the back, between the shoulder blades, where it cannot be reached by the animal. Should a monthly dose be missed, it should be administered as soon as possible. No matter what, only one dose should be administered within a 30 day period.

Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.