Brand: EFFIPRO ® DUO

Company: VIRBAC


FORMULATION: «spot-on» solution for topical administration on the back of the animals (also called pipettes, squeeze-ons, drop-ons, etc.)

ACTIVE INGREDIENT(S)

CHEMICAL CLASS of the active ingredient(s):


INDICATIONS: DOGS and CATS


PARASITES CONTROLLED* (spectrum of activity)

* Can be slightly different in some countries: read the product label!


RECOMMENDED DOSE*

  • Dogs, small 2 to 10 kg bw: 1 pipette with 0.67 mL containing 67 mg fipronil and 20.1 mg pyriproxyfen
  • Dogs, medium 10 to 20 kg bw: 1 pipette with 1.34 mL containing 134 mg fipronil and 40.2 mg pyriproxyfen
  • Dogs, large 20 to 40 kg bw:  1 pipette with 2.68 mL containing 268 mg fipronil and 80.4 mg pyriproxyfen
  • Dogs, very large 40-60 kg bw: 1 pipette with 4.02 mL containing 402 mg fipronil and 120.6 mg pyriproxyfen
  • Cats 1-6 kg bw: 1 pipette with 0.5 mL containing 50 mg fipronil and 60 mg pyriproxyfen
  • Large cats: >6 kg bw 1 pipette with 1 mL containing 100 mg fipronil and 120 mg pyriproxyfen

* Can be slightly different in some countries: read the product label!


SAFETY

  • LD50 (acute oral) in rats: n.a. for the formulation; 97 mg/kg (for fipronil)
  • LD50 (acute dermal) in rats: n.a. for the formulation; >200 mg/kg (for fipronil)
  • Estimated Toxicity Class according to the WHOU unlikely to present acute hazard (learn more)

Suspected poisoning? Read the articles on fipronil safety and pyriproxyfen safety in this site.

WARNING !!!: Never use on cats pipettes approved only for dogs. Never use on small dogs pipettes approved for large dogs. Learn more about spot-ons and their safety.

You may be interested in the following articles in this site dealing with the general safety of veterinary products:


RESISTANCE PREVENTION

Risk of resistance? YES, low in fleas, mainly the cat flea, Ctenocephalides felis.

So far there are no confirmed reports on flea resistance to dinotefuran. However, fleas have developed resistance to several other insecticides (e.g. carbamates, organophosphates and pyrethroids) and are certainly capable of becoming resistant to dinotefuran as well.

There are only very few confirmed reports on flea resistance to fipronil, more than 25 years after its introduction for flea control. But there are rumors that the number of product failures is increasing, mainly in the US.

Fleas have developed resistance to several other insecticides (e.g. carbamates, organophosphates and pyrethroids) and are certainly capable of becoming resistant to dinotefuran and fipronil as well. Experience shows that prolonged and uninterrupted use of any insecticide on fleas bears the risk of resistance development.

There are no reports on resistance of fleas to pyriproxyfen.

This combination of three active ingredients of different chemical classes makes sense regarding resistance prevention, because it means attacking fleas through three different mechanisms of action, which is vastly assumed to help preventing or at least delaying resistance development.

Alternatives to prevent flea resistance through product rotation:

*F = effective against fleas; T = effective against ticks.

These alternative products may not be available in all countries, or may not be available as spot-ons.

Resistance of fleas to carbamates, organophosphates and pyrethroids is not uncommon in several countries, including the USA.

There are no reports on resistance

Learn more about resistance and how it develops.


MARKETING

Are the active ingredients of this product ORIGINAL* or GENERICS**?

  • Fipronil: GENERIC (introduced in the 1990s by RHÔNE MÉRIEUX)
  • Pyriproxyfen: GENERIC (introduced in the 1980s by SUMITOMO)

*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this product is marketed (maybe under another TM): USA.
GENERIC BRANDS available? YES, in some countries

Click here to learn more about GENERIC vs. ORIGINAL drugs.


COMMENTS

EFFIPRO DUO is a once-a-month flea spot-on for dogs and cats from VIRBAC containing generic fipronil and pyriproxyfen.

Administered about every 4 weeks, this product controls established flea and tick infestations and prevents flea populations to develop in the pets environment, but only if all the dogs and cats in the same household are treated against fleas.

Fipronil is a broad-spectrum insecticide and acaricide belonging to the phenylpyrazoles introduced in the late 1980s (by RHÔNE MÉRIEUX → MERIAL). It is effective against both fleas and ticks. It is massively used in pets and agriculture, and also moderately used against household pests. In some countries it is used in livestock as well.

Pyriproxyfen (Nylar) is a veteran insect development inhibitor (IDI = IGR = Insect Growth Regultor) introduced in the 1980s (by SUMITOMO) scarcely used in pets. Its only effect is to stop development of flea eggs and larvae. It has no protective effect whatsoever against adult fleas and is ineffective against ticks. The logic of combining it with fipronil is to ensure that if a few fleas survive the killing effect of fipronil (what usually happens) development of their offspring is inhibited, because the eggs of the surviving fleas will not complete development.

Numerous other flea spot-ons contain methoprene as an IGR, which is rather UV-sensitive and gets quickly degraded when exposed to sunlight. In this product pyriproxyfen is used as an IGR, which is less UV-sensitive than methoprene and thus ensures a longer residual effect.

This combination of two active ingredients of different chemical classes makes also sense regarding resistance prevention, because it means attacking fleas through different mechanisms of action, which is vastly assumed to help preventing or at least delaying resistance development.

Topical products (mainly spot-ons and insecticide-impregnated collars) have some advantages over systemic products (mainly tablets for oral administration and injectables):

  • Most topical products kill or sterilize the parasites before they bite and suck blood on the pet, whereas systemic products kill or sterilize the parasites only after their blood meal.
  • Topical products cannot be vomited.
  • Spot-ons and collars are very convenient to administer.
  • There is a larger choice of topical products.

But topical products have also some disadvantages:

  • Topical products contaminate the pet's hair coat and it is advisable for children and also adults to avoid contact with the pet for several days after treatment.
  • Topical products may not control parasites in some parts of the pet's body (e.g. the ears, below the tail, between the legs, etc.), whereas systemic products reach the blood-sucking parasites through the blood wherever they are.
  • Efficacy of topical products may be reduced or shortened through exposure to dirt, sun, shampooing, washing, rain, baths, etc., whereas efficacy of systemic products is independent from these factors.

For an overview and a list of the most popular pet antiparasitics for flea, tick, lice and/or mite control click here.


DISCLAIMER

This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.