ANTI-TICK AND FLEAS
Fipronil is most widely used ectoparasiticide in India. Vets use it on regular bases and distribution companies call it safest ectoparasiticide product available in the market. But have you ever wondered how safe is fipronil for your dog and in what quantity they should use? Because none of the product manufacturers has given an effective dose and reliable safety instructions with their product. And few people use it indiscriminately even using 3-4 times the dose needed to be sprayed on your dog.
What is Fipronil?
Fipronil is a broad-spectrum insecticide. Fipronil effect central nervous system of insects by blocking GABA gated chloride channels and glutamate-gated chloride channel. It is 700-1300 times more toxic to insects than mammals. Because of its affectivity to control ticks and fleas, it is used extensively in dogs and cats.
Fipronil is lipophilic compound and gets deposited in sebaceous glands in dogs, thereafter get released slowly. This makes single application effective for long period.
Products and packaging:
Many commercial ectoparasiticide products containing fipronil is available in the market. Few popular brands are Fiprofort (SAVA Vet), Freedom spray (Venkys), Protector (Cipla), Effipro (VIRBAC), Frontline Plus (Merial).
Basically, Fipronil products are marketed in two forms:
Spray: It has concentration of 0.25% w/v
Spot-on: It has concentration of 9.8% w/v
Effective dosage and effective period:
However effective dosage is not mentioned on any product. We derived effective dose from research papers. Based on trials effective dose for fipronil is 13mg/kg body weight.
Effective period for spray is 12 weeks for fleas, 4 weeks for Flea allergy dermatitis, 3 weeks for ticks; for spot-on 4 weeks for fleas and flea allergy dermatitis and 2 weeks for ticks.
Absorption and toxicity:
Fipronil is not readily absorbed through the skin. Only 1% is absorbed into skin application. Orally only 15-50% is absorbed and rest is excreted in feces.
Based on trial done on Beagles no adverse effect was found on 0.2mg/kg/day given orally for one year which is definitely more than absorption through an effective dose of 0.13mg/kg (1% absorption).
Fipronil is thus tolerated very well in dogs.