What is fipronil?
Fipronil (brand names: Frontline®, Barricade®, Easyspot®, Effipro®, Sentry Fiproguard®, Parastar®, PetArmor®, Pronyl OTC®, Spectra Sure®, and many others) is a topical medication used to treat fleas, ticks, and chewing lice infestations in dogs and cats. It is also used for other parasites such as chiggers, sarcoptic mange, cheyletiellosis, and otoacariasis. Fipronil is often used in combination with other medications to treat a variety of topical parasites.
Its use in cats and dogs to treat certain parasites is “off label” or “extra label”. Many drugs are commonly prescribed for off-label use in veterinary medicine. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label.
How is fipronil given?
- Fipronil is applied topically to the skin or haircoat in the form of drops or spray.
- Drops: Apply directly to the skin by parting your pet’s hair between the shoulder blades and at the base of the neck, then applying the applicator tip directly to the skin and squeezing the applicator to empty the contents.
- Spray: Apply by ruffling your pet’s coat with one hand while spraying the skin and coat with the other hand. Do not spray directly onto the head or face; spray on a gloved hand and then gently rub into the hair on the head.
- Do not get in your pet’s mouth or eyes, and do not apply to irritated skin.
- When using the spray form, use in a well-ventilated area.
- Do not bathe your pet with shampoo within 48 hours of application.
- For best effect, avoid getting your pet's coat wet and minimize exposure to sunlight for 24 hours after application.
- Avoid human contact with skin, eyes, or clothing; wear gloves when applying, and avoid contact with your pet until dry.
- If the medication gets on your skin, wash well with soap and water.
Fleas will start to die 4 to 8 hours after application. Ticks may take 12 hours or longer to die and fall off, and improvement in clinical signs should follow.
What if I miss giving my pet the medication?
Apply the missed dose as soon as you remember, and then wait the recommended amount of time between doses. Never give your pet two doses at once or give extra doses.
If prescribed for monthly application, give the dose as soon as you remember and start a new monthly dosing schedule. For example, if you forgot to give your pet their dose on June 1 and remember on June 18, give the dose on June 18, and start a new monthly schedule. Give your pet their next dose on July 18. Do not give your pet two doses at once. Contact your veterinarian if you are concerned about a missed dose.
Are there any potential side effects?
Side effects are uncommon, but may include:
- temporary irritation at the application site
- an allergic reaction of the skin (rare)
This long-acting medication lasts for at least 4–6 weeks and may last longer in pets with kidney or liver disease.
Are there any risk factors for this medication?
Fipronil should NOT BE USED in:
- pets that are allergic to fipronil
- puppies or kittens younger than 8 weeks of age
- rabbits
Fipronil should be USED WITH CAUTION in:
- pets that are old, sick, or frail
Are there any drug interactions I should be aware of?
There are no specific drug interactions with fipronil. Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking.
Is any monitoring needed with this medication?
No specific monitoring is required while your pet is taking this medication. Your veterinarian may monitor your pet to be sure that the medication is working.
How do I store fipronil?
Store this medication away from heat or open flame.
What should I do in case of emergency?
If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility.
