Activyl: Something New in Flea Control

Activyl uses new technology in flea control

If you’ve had to deal with fleas on your dog or cat, you’re probably already familiar with the common topical products used to control these pesky parasites. Maybe you even feel that the fleas in your area have become immune to all the standard treatments. Now there’s something new: Activyl and Activyl Tick Plus. According to the manufacturer, Merck Animal Health, it’s the first and only flea product to use metabolic activation or “bioactivation.” This new technology available only in Activyl uses the enzymes inside the flea itself to activate the flea-killing power.

How does Activyl work?
The active ingredient in Activyl is indoxacarb, which has not been used before, so there is no known problem with fleas being resistant to the product. You apply Activyl to your pet once a month, just like any other topical flea and tick product. Once applied, Activyl spreads through the natural oils in your dog or cat’s skin and coat. When a flea lands on your pet, it takes up the Activyl where it changes inside the flea into Activyl’s fully active form; the flea then becomes paralyzed and dies. Acitvyl remains on the surface of your pet’s skin, not in the bloodstream; therefore, fleas do not have to bite your pet to be affected. Since the majority of the activity occurs inside the flea, your pet’s exposure is lessened.

In addition to killing adult fleas, Activyl also prevents flea eggs and larvae from developing which effectively breaks the flea life cycle. Activyl begins killing fleas within hours of application and continues working for four full weeks. It’s waterproof, quick drying, fragrance free and is effective even after swimming, exposure to sunlight, or bathing your pets. However, for maximum effectiveness, you should not bathe your pet or allow your pet to swim within 24 hours of application.

Does Activyl treat ticks?
If you’re concerned about ticks, you can use Activyl Tick Plus for dogs only. It has all the benefits of Activyl, but with the addition of permethrin, it also repels and kills adult ticks on contact.

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  1. Barbara McDonaldJuly 4, 2014 at 10:11 am

    We applied Activyl to our 7 lb rat terrier on Wednesday and it wouldn’t dry, plus she started limping and acting like she was going to throw up. It’s been two days now and nothing has changed. I gave her a bath in Dawn which was suggested to do. Help! What to do???

  2. Dr. Michael Dym, VMD veterinarianJuly 4, 2014 at 6:21 pm

    Best to see vet for evaluation and supportive care.

  3. Will the ticks fall off when they die or will I need to remove them in the same manner as a live tick would be removed?

  4. They fall of on their own, I applied Activyl to my 70lbs lab and it’s working like a charm. So far the only thing that has worked on her.

  5. How long after application does it take activyl start to killing fleas?

  6. Dr. Michael Dym, VMD veterinarianSeptember 8, 2014 at 3:31 pm

    Usually within 12 hours

  7. How long after using is it okay to give my dog a bath?

  8. Is Activyl effective against chewing lice on cats? Thank you!

  9. I tried Activyl after reading this blogpost but have found it to be not as effecient as Frontline Plus. I still have to use Frontline Plus. May be it is a factor of environment or something similar that is making it inefficient for me.

  10. I also am asking is Activyl effective against chewing lice on cats???? thanks

  11. We have tried every flea medicine out there and nothing has worked! Our friend suggested Activyl and we are so excited how well it works. We have told everyone we know about it. It’s so worth the extra dollar! I hope they never discontinue this product.

  12. And to reply to the previous post, my vet said not to bath my dog 48 hours before or after treatment.

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