About Fleas

In addition to causing itching and discomfort, left untreated, fleas can cause medical problems in pets including an allergic reaction called flea allergy dermatitis (FAD) that can result in hair loss, skin inflammation and irritation, and severe scratching. In large numbers, fleas may cause anemia from blood loss, which can be fatal if your pet is young, feeble, or small in size.

Flea life cycle

The average flea life cycle takes between 3 and 4 weeks, but can last 180 days (6 months) depending on temperature and humidity.1


  1. Eggs - Female lays 40-50 eggs per day on the host.1 Eggs fall off into the environment. Eggs hatch into larvae within 2 weeks.
  2. Larvae - Larvae feed on flea fecal matter in the environment. Larvae can ingest tapeworm eggs.
  3. Pupae - Within a week, larvae form a cocoon and pupate. Adult fleas emerge from the pupae and begin feeding as soon as a host is found.
  4. Biting Adults - Adult fleas feed on host. Females need blood meal to reproduce. Fleas may transmit disease-causing organisms during feeding.


Flea life cycle

Protection from fleas

K9 Advantix® II contains a combination of imidacloprid, permethrin and pyriproxyfen, an insect growth regulator (IGR) which protects your dog from fleas at ALL life stages and  prevents further flea infestations.

K9 Advantix® II:

  • Kills ALL life stages of fleas – prevents development of fleas, flea eggs, larvae (maggots) and pupae (cocoons)
  • Kills fleas through contact so fleas don’t need to bite to die
  • Kills fleas quickly – within 12 hours, and kills reinfesting fleas within 2 hours
  • Prevents fleas on a treated dog from reinfesting the home
  • Can be used on puppies as young as seven weeks of age
  • Is waterproof




1 Dryden, M, Payne, P, and L. Zurek. Pests that Affect Human Health; Fleas Infesting Pets & Homes. Kansas State University Agricultural Experiment Station and Cooperative Extension Service, MF-760, September 2003.

K9 Advantix is a registered trademark of Bayer.

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It did not work for ticks I used advantix II on my dog about 10 days ago. She never got wet, no bath, no rain. Today I took her to the groomer and they found a tick on her. Fortunately it was only a brown tick. Will never buy this again. August 11, 2012
We still have ticks Even after applying this product to my 22lb dog...I am pulling ticks off of him at least 2 times a week! I was hoping this would prevent that. He is mostly indoors, but we take him for walks in areas that obviously have ticks. I don't know what else to use. I am very disappointed that a brand that claims to prevent ticks is not working for us. I haven't seen fleas though, so I guess part of it is working. August 1, 2012
Didn't work I put K9 Advantix 2 on my 4 month old Golden Retriever puppy and even the next day she had ticks. I am so tired of pulling ticks off of her. It's been 2 weeks yesterday that I applied it and everyday I am pulling off every varitation of tick out there. I am so dissapointed K9 Advantix is suppossed to be the best. It's not. I paid $50 for my 4 month supply and will not be buying it again. July 17, 2012
Didnt work for me I have been using this product faithfully on my two shelties for the last two years, Well, last night I discovered them covered with fleas..... I will not be buying this product anymore. July 16, 2012
Doesn't work! I applied Advantix to my Husky mix dog 1 week ago. Today while she was in the house a huge engorged tick fell off of her. Gross!! It was not dead. I took her outside and pulled off 15 more slightly engorged ticks. None of which were dead. This product does not work! July 15, 2012
Does NOT work! Waste of money!!! I have been using K9 Advantix on my dog for the past 3 months and it does not work at all. I switched to Advantix from PetArmor which was just as bad but more affordable. I thought paying so much for a product would mean something but after 3 months I am very disappointed. For instance, I put Advantix on my dog, Riley, five days ago and there are fleas all over him. I do not expect Advantix to be a miracle worker and perhaps I could maybe understand if he had fleas after a few weeks but five days later??? According to the label, Advantix is supposed to kill fleas within 12 hours of application. That is completely false. I'm tired of spending so much money on products that do not work and this is one of them that I will surely never use again!! Perhaps if your dog stays indoors his entire life and never goes into a yard then Advantix might be useful. Other than that its a waste of money! July 15, 2012
Doesn't work Last month I bathed and brushed both my dogs(X-large 90 & 110 lbs and appllied K9 Advantix as instructed. I have pulled 2 ticks off of my yellow lab; one a week after I applied and one 2 weeks after I applied. I'm not very happy as this stuff isn't exactly cheap. July 15, 2012
Wonderful product! I can't say enought about this product. Love it! Thank you for helping to protect my lab from nasty ticks!! July 14, 2012
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