Advantage vs. Revolution vs. Sergeants Gold

Question
Hi, Jessica.  You've helped me twice before (once about moving my elderly kitty to a new apt. -- you suggested that Feliway stuff) and I really appreciate your sharing your expertise.

This time I'm wondering if it's okay to use this product to prevent fleas on my cats.  (Two of the three do go outdoors sometimes.)  This is called "Sergeant's Gold, Squeeze-On for Cats and Kittens" and it says 5-way protection -- kills fleas and deer ticks, kills flea eggs and larvae, repels mosquitos.  It is a tube with the twist-off cap type.

In the past I've always used Revolution or Adantage (or Advantage-Plus).  But it's often not inconvenient to get to a pet store or vet where I can get those.  So I just saw this "Sergeant's Gold" at Safeway and wondered if it is as effective and safe.  

If this helps, it says the active ingredients are etofenprox 55% and pyriproxyfen 2.2%.  I don't have a clue what those are, but I noticed it's different than on the Advantage label.

Thanks again, you are tops!  :-)

Answer
Hi Susan!  Hope all is going well.

Pyriproxyfen doesn't bother me so much.  It's an IGR (Insect Growth Regulator).  It doesn't kill fleas but prevents young from developing.  There's no evidence it's toxic when used according to directions.

However, etofenprox is a pyrethroid.  Although to differing extents, all pyrethroids are toxic to cats.  Etofenprox isn't as dangerous as some other pyrethroids, but I have to say I would not personally use it on my cats.  I applied one pyrethrin-based treatment to my cats before.  Most of the cats were okay, but one started foaming at the mouth, went into seizures and was unconscious before we could get him to the hospital.  He did recover after 3 days in the ICU.  Because of that experience, though, I will not use anything that contains a pyrethroid.  I'm an Advantage gal all the way.