How Long Does Flea Medicine Take to Work?

Dog Still Have Fleas: How Long Does Flea Medicine Take to Work

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Fleas are such a problem in warm humid areas, particularly in high density living with lots of animals and free-roaming felines. Yes, we can often blame the felines for this one, but that is a simple view and it’s not the whole story.

If we step back and think of them, fleas are interesting parasites. They are exceptionally successful at outsmarting us at every turn. It would be nice to think we might just put a month-to-month flea product on our animal then forget it, however this is not constantly enough, especially in warm climates. If you seek a more natural method we will also give a couple of suggestions of what will and won’t work for your animal.

I ‘m Using Flea Control, Why Are There Still Fleas?

The majority of flea products eliminate adult fleas and stop them laying eggs, but none work immediately. In reality most take around 8-24 hours to kill each flea that gets on your animal. Unlike numerous parasites, most fleas reside in the environment, not on your animal. And there are constantly a lot of brand-new fleas waiting in the wings, ready to replace those that are killed.

If you are counting on a flea hair shampoo, collar or among those cheap top-spots in the grocery store, you are squandering your time and money too!

Typical Problems

  • A small break in flea prevention, even if that was during winter season, can cause big problems in the future. Fleas lay 50 eggs every day, so even being a couple of days late with your flea prevention is all it requires to build up a collection of flea eggs.
  • Not all flea eggs hatch at the same time, they can last for months in the environment. Those flea eggs will gradually hatch over the following months and return to haunt you!
  • Stray felines entering the yard, a going to flea-infested dog or neighbours felines and dogs can be a source of adult fleas, and those dreadful flea eggs.
  • Sydney has the ideal environment for fleas to make it through year-round, so the common practice of stopping flea treatment over winter season can cause issues over summertime.
  • Bathing more regularly than weekly can remove top-spot flea items from your family pet’s skin and hair. If your animal swims, think about changing to a flavoured chew like NexGard, Bravecto, Comfortis or Panoramis.

What Do I Do Now?

  • If you are seeing small numbers of fleas, yet your dog does not seem that worried, continue with your regular monthly flea treatment throughout the year and ultimately you will begin to see less fleas.
  • If your dog is exceptionally sensitive to fleas and develops hot-spots or has allergies, to start with switch to Comfortis. This regular monthly flea tablet is the fastest-acting flea item available.
  • An option to Comfortis is utilizing Capstar (or a similar item consisting of nitenpyram) every 2nd day, together with your routine flea medication. Capstar is perfectly safe to use with any of the other flea and tick products, including our favourites, Bravecto and NexGard.
  • Vacuum the whole house thoroughly, including under beds and furniture. Pay specific attention to areas within a couple of metres of your pet’s bed.
  • Use a flea bomb for each single room in your house, but make sure you do that great comprehensive vacuum first to get rid of any particles of dust that might secure the flea larvae from the bomb.
  • The flea bomb will just reach those areas where the mist settles. Under the bed and under furnishings may have to be dealt with separately with a hand-held flea spray like Black Raid or Purple Mortein.


Treatment of the outdoors is more complicated. Ideally all animals surrounding your home or business needs to be on flea control, consisting of those stray cats! Warm, dark areas are often flea nests so have a look at the lawn and where your animal spends lots of time. Does your dog oversleep the mulch because dubious corner? Does he retreat under the house on hot days?


To deal with fleas outdoors:

  • Sweep up leaves
  • Scare off those roaming felines or purchase your neighbour some flea avoidance for her 20 cats
  • Keep yards short
  • Limitation making use of mulch or fence these areas off
  • Offer your pet a cool, flea-proof bed like a trampoline bed to rest on outdoors
  • Block off the area under the house or down the side of your house
  • If your dog has a kennel, avoid carpet in the base and use an old towel you can maker clean weekly
  • Toss out any old couches or mattresses your pet naps on exterior
  • Pool salt can be used as a dessicant or drying representative to kill flea eggs and pupae, but can be irritating to your dog’s skin and is not excellent for plants. You will eventually have to block off the area if you can
  • Consider a professional pest company, however all the above will make any insect spraying a lot more efficient

Animal Bedding

Ensure any family pet beds can be washed in their totality on a hot cycle in the washering (over 60ºC for more than 10 minutes). Do a good wash of anything your dog sleeps on each week. It is insufficient to simply clean the cover of the bed as the fleas will burrow down into a mattress or foam. Trampoline dog beds are excellent, flea resistant beds for larger dogs. For smaller sized dogs, use a good machine-washable bed.

Natural Solutions

Often in the hunt for a more ‘natural’ way to secure our family pets, all sorts of unusual and fantastic recommendations are made on the web. A few of these are quite honestly really unsafe. At best they can be inefficient and divert your attention from the things that do work. Flea products have years of research into safety and have very strict manufacturing controls and are much safer than all the other whacky suggestions. Never under any scenarios spray your pet with tea tree oil (which is toxic if consumed), lemon juice (yikes! that would need to sting!), garlic (again, harmful!), apple cider vinegar and citronella (which is used as a deterrent in bark-collars due to the fact that dogs dislike the smell!).

The best natural solution for fleas is a flea comb, cleaning bedding on a hot cycle in the washering once a week and vacuuming every few days. Then follow the directions above for keeping flea numbers down in your yard. There is a powder called Flea Busters that is based on boric acid that can be swept into the floorboard gaps or carpets to serve as a dessicant for flea eggs and larvae. Simply make sure you vacuum it all up before your animals or kids walk on it.

Key Points to Remember

  • Flea medication can look like it’s not working since nothing kills fleas quickly
  • Treat the environment with flea bombs and regular vacuuming
  • Wash animal beds weekly on a hot cycle
  • Keep yards brief and lawns swept
  • If you bathe your animal more than weekly, top-spot flea products might not work

Also read: Fleas on Dogs


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References and used sources

D. Roberts (Junior Expert)

He is a specialist in the field of veterinary medicine, and pet care. Believes that the person responsible for each pet, which was taken into the house, and therefore should study his behavior, means of determining health status and methods of first aid.

Pet Health