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My dog still has fleas a week after K9 Advantix. What should I do?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | unneutered | 9 months and 1 day old

It's been a week and a couple days since applying k9 advantix 2. Still has a couple of fleas. Around the chest/stomach area only. What should I do?

4 Answers

Most Helpful Answer

Answered By Jennifer Summerfield, DVM CPDT-KA

Veterinarian, Certified Dog Trainer

Published on August 27th, 2016

If you're still seeing fleas after more than a week, I would be concerned that the K9 Advantix may not be working very well - it's usually one of the most effective topical medications for most dogs, but some will still have fleas. You can get an oral flea/tick medication like Nexgard or Bravecto from your vet that will be more effective, and you can give it right away - these are safe to administer along with K9 Advantix or other topicals if needed. If there are a lot of fleas in the environment, this could also be a reason that you are still seeing some - in this case, you may need to treat your house and yard for fleas or have an exterminator do this professionally to make sure they are gone.

6Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Destini R. Holloway, DVM
Veterinarian
I would recommend treating the home with a flea fogger found at your local Home depot or Lowe's. Also treating the yard is an option to help control the fleas in the environment. Max may just be going in an area that is overpopulated with fleas.

If this still doesn't work, then I would consider switching to a different product to see if will work better. Some good options are Bravecto, Nexgard, and Comfortis.

For now you can purchase a Capstar tablet to get rid of all the fleas on him within the next 24 hrs. This is not a preventative but helps control particularly high flea loads on pets and is used during times like this when it is not safe to reapply a topical preventative.

You can safely re-apply most topical flea products every 2-4 if needed to re-dose early. You can also call an Advantix rep on the hotline number just to make sure their product is safe for every 2 week application.
5Pet Parents found this answer helpful
Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on August 5th, 2017
I'm so sorry you are facing this! Fleas are a difficult thing to deal with, and sometimes it takes more than one visit from the professional to kill them all. My brother had to have an exterminator visit three times before all the fleas were gone from his home. It's safe to apply another dose of the K9 Advantix to Lady, and I would do that now. You can also give her Capstar, which is a one time pill that starts killing fleas in 30 minutes and is safe to give along with the K9 Advantix. I would call the professional again to come out for another visit. Again, I'm sorry you are dealing with this :-(
1Pet Parents found this answer helpful
Answered By Anna M., DVM
Veterinarian
Published on July 7th, 2017
No, if you are seeing fleas I would encourage treatment. I recommend using a different product with a different active ingredient from k9 Advantix. You could use another topical such as Revolution, or an oral product such as Nexgard or Bravecto. I hope this helps!
1Pet Parents found this answer helpful

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Related Questions

Health & Wellness

Why is my dog still itchy and has fleas despite Advantix treatment?

If you’re noticing increased itching in that area and you found a flea, you may try switching the flea prevention to see if that helps. Fleas can become immune to products. The top products on the market are oral products such as Nexgard and Simparica. Most pets can use these products but you should talk with your veterinarian before switching. They are administered once a month and at this point appear to work very well. If the itching goes away, then you know it was related to flea bites. Best of luck.

Updated on September 23rd, 2025

My dog has fleas after Advantix. Do antibiotics affect flea meds?

The antibiotics should not weaken the flea treatment. If you did not treat your house, especially where she spends most of her time, there are probably still fleas in your house and they are jumping back on her. The fleas should die once they bite her but you will continue to see fleas until the environment is treated, too. You will need to treat the environment with a product that has a growth regulator and continue to use the Advantix on her monthly.

Updated on September 23rd, 2025

Why isn't K9 Advantix II working for fleas & my dog's ears are itchy?

You'll want to be sure to the environment the Pets are in has been treated too. The fleas will die after they've bitten the Pet. This helps to kill the adult fleas. You may be finding fleas from the eggs that were laid at the time of application who are now growing into maturity. If there are many, you'll want to treat the house and yard and visit your local Veterinarian to discuss other options. For the ears, if you see any redness or inflammation you'll want to visit your local Veterinarian as soon as possible. They may have a yeast or bacterial infection that is causing discomfort.

Updated on September 23rd, 2025

Advantix not working. Can I give Nexgard soon after last dose?

I’m sorry it’s not working! I would give Bruzer Capstar. It’s a one time pill that starts killing fleas in 30 minutes, and it’s safe to give now. Give it once a day until it’s been a week since you applied the Advantix, and then give him the Nexgard. Also be sure to disinfect your home, as fleas live in the environment, not on the dog. Wash his bedding in hot and soapy water, and vacuum all the carpets and furniture. Use a spray like Indorex or a flea bomb to kill all the fleas in the house. I hope this helps!

Updated on September 23rd, 2025

Health & Wellness

My dog has fleas. Can I use Capstar and K9 Advantix together?

You can use both products on the same day so it is fine to start the Advantix at any time. There are better products that Advantix. Top products for dogs are oral products such as Simparica and Nexgard. Top products for cats are topicals such as Revolution and Cheristan. There is also an oral product called Comfortis that both dogs and cats can take. You will need to switch all the pets over to a good flea product. Make sure to discuss these products with your veterinarian first. These products are generally safe for all pets but there are some conditions which are contraindicated for the oral products. Cleaning up and treating the house and yard will also help but it will not clear all the fleas. The main control is making sure the pets are on good products. This is what will ultimately stop the infestation. Also remember every female fleas lays about 50 eggs a day and it could take up to 6 months before the eggs hatch. Therefore, you will need to treat for at least 6 months. Best of luck and please feel free to post any additional questions.

Updated on September 23rd, 2025

Health & Wellness

Is it safe to switch from Frontline Plus to K9 Advantix II for fleas?

Since it's been two weeks, yes it's fine to apply the Advantix now. I would also give Barney Capster. It's a one time pill that starts killing fleas in 30 minutes. You will also have to disinfect the environment. Wash his bedding in hot soapy water, and vacuum the furniture and carpet surfaces. You can use a spray to kill fleas in the house, such as Indorex, or a flea bomb would work well to kill the fleas in the home. I hope this helps.

Updated on September 23rd, 2025

My dog still has fleas after Bravecto. What should I do next?

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Fleas can be frustrating to eradicate even when using a quality product like Bravecto. You may wish to consider a product like Capstar or even a topical flea medication in addition to the Bravecto. Products like Frontline Gold, Vectra and Advantix tend to work well. The flea life cycle sometimes necessitates that you also treat your household and even your yard to fully eradicate the infestation. Regular laundering of pet bedding can help but you may still end up needing to have an exterminators help. Finally, make sure all pets in the household are treated with a safe, quality flea preventative as often house cats that have not been treated can harbor fleas. Good luck!

Updated on September 23rd, 2025

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