The Top 5 Reasons You Are Still Seeing Fleas

Fleas, fleas, fleas and how to treat them

Treating monthly and still seeing fleas? This might be why…

You’ve been doing the right thing by treating your pet with a preventative treatment on the correct schedule but hang on, you’ve just seen a flea. How has this happened? At VetBox we get this question often and we know it can be frustrating. Rest assured you are doing the right thing by treating your pet, but here are our top 5 most common reasons you may still be finding fleas on your pet and in your home. 

  1. You need to treat all pets in the home.

To successfully get rid of a flea infestation, ALL pets in the home need to be treated, not just the pet who seems to be affected. Some people may see fleas on multiple pets, but more often there is one primary offender who seems to be the flea favourite. This is why it’s vital that all your pets are treated with an appropriate flea treatment each month. 

  1. You need to treat them for long enough. 

It’s not uncommon for pet parents to be concerned when fleas aren’t gone IMMEDIATELY. It’s completely understandable as fleas are 1) unappealing and 2) irritating to you and your pets. That being said, consistent treatment is typically needed for three consecutive months to have the best chance beating a flea infestation. This has to do with the flea life cycle itself. Fleas are incredibly  persistent. They are fantastic at laying eggs that turn into larvae that are especially hard to get rid of. These live in your carpet, bedding, furniture, etc. and hatch into adults in the weeks to come. One female flea can lay 2,000 eggs in her lifetime. In moderate climates (not too hot and not often below freezing), our pets need to be treated with a preventative monthly all year round to break the flea cycle and keep them away. 

  1. You need to use an effective product. 

Not all products are right for every pet. For starters, it’s important that we as vets remind owners to ensure the product they are planning to use is made for either a dog or a cat. There are many products made for dogs that are very toxic to cats, so ensure you have the right product for the right species. Do not split a dose between pets, this will not provide the right amount of treatment to do its job. Some pets may do very well with one type of flea treatment whereas others may need a different product. Not all flea treatments contain the same drug and not all pets respond to every drug the same. You may be one of the fortunate ones that can use an over-the-counter treatment successfully, however some pets need a slightly stronger prescription treatment from their veterinarian. Unfortunately in our veterinary experience we have not found “natural products” to yield much success.

Important note: When using topical or spot-on treatments, you should not bathe your pet or let them swim within 5-7 days of application. These treatments rely on a normal intact fatty acid layer in the skin to be absorbed and spread. Bathing or swimming can disrupt this layer, or even just wash the product off before it is absorbed!

  1. You might have missed a month….or two…..ok nine…

The majority of flea treatments are created to be administered once every 4 weeks. Missing the due date by a few days here or there is typically ok, however if you miss a treatment for your pet and get to weeks 6, 7, or 8 on from the last treatment your pet is no longer protected. One tip is putting a reminder on your phone each month to give flea/wormer treatments so you don’t forget. VetBox subscriptions go one better because you get that friendly reminder from the team each month when your box arrives. Plus treats…bonus!

  1. You need to appropriately treat YOUR HOME!

This may be one of the biggest issues that we when people are having trouble with fleas at home. Owners get halfway there by diligently treating their pets, but forget an equally important part – cleaning their home itself. As mentioned above, flea eggs are produced by the hundreds and are fabulous at shedding off your pet into the house. These will mature into larvae that hide and become dormant in places like bedding, carpet, and furniture. Eventually if not also battled, they will become adults in weeks/months ready to start the life cycle again. We strongly encourage vacuuming all surfaces, washing bedding/blankets both human and pet, in hot water, and considering a safe environmental spray for carpeted areas and upholstery that will inhibit flea eggs and larvae. Often one round of deep cleaning is enough, but repeating these steps may be needed. A quick note, these sprays are made for your home NOT your pet! Keeping pets confined to an area where you have not sprayed while treated areas dry for a few hours is typically recommended. Following manufacturer guidelines and vet guidance is always best. 

A few final tips…

Virbac Animal Health make an effective and safe spray for your home that is widely available including on Amazon, called Indorex Spray. This is a product we often recommend to pet owners as an option in severe home infestations. *Reminder: Please follow product recommendations for application in your home. This is not a pet product!*

No one likes fleas and we want them off your pets and out of your home. Once again the best bet for success is responsible and regular monthly preventative treatments to keep us all happy and flea free. 

Dr. Kirsten Ronngren, DVM – MRCVS

Vet at VetBox

Get your VetBox subscription and start beating fleas today.

Fleas 101 and how to treat them

How to treat your pets for fleas

A Crash Course for Pet Owners

“I’ve never seen a flea. My pet doesn’t have fleas.” As vets we’ve heard this many times and wish it was true. Unfortunately that’s simply not the case and fleas are one of our most common external parasites in dog and cat patients. All pet owners who have experienced them will agree that live fleas are gross, but what many don’t realise is there are other risks in addition to fleas’ ability to cause discomfort. That’s why consistent flea prevention is so important and this post will cover all the main health risks that fleas pose for your pets, and also to you/your family. 

First let’s cover the big one, the major reason why many owners end up at the vets. Your dog or cat has live fleas and they are ITCHY! Flea bites are uncomfortable and cause itchiness in our furry family members but also the rest of the family. Fleas aren’t picky about where their meal comes from (blood) and they will bite any warm body near them, meaning you and your family are fair game for these parasites. Animals will obsessively lick, bite, chew and can even become extremely stressed when infested with fleas. Not to mention they’ll be keeping you up at night doing so. 

Now that we’ve covered the most common reason owners reach for flea prevention,  it’s even more important we touch on the things people may not know about that can create an even bigger problem.

Flea Allergy Dermatitis

 A step above your average itchy flea bite is referred to as flea allergy dermatitis (FAD). Some pets have an immune hypersensitivity or allergy to flea saliva, and when bitten a more severe local reaction will occur. Affected animals will lick and chew themselves in response to a bite to the point of hair loss, severe redness and even secondary bacterial or yeast infections. These pets absolutely should be treated regularly for fleas to decrease the chances of experiencing these types of outbreaks, as they are often painful. Pets that suffer from FAD often need to seek veterinary care for topical and/or oral medications like antibiotics, anti-inflammatories, sprays, and shampoos to help treat the skin. 

Environmental flea infestation

Just because you can’t see fleas doesn’t mean they aren’t there. Live adult fleas are small and quick! Adults can be seen with the naked eye, are dark brown in color and only a few millimeters in length. They like to jump around but also burrow deep within the fur to plan their next “blood meal” (bite). Eggs however, can’t be seen so easily and are produced in large quantities which can remain on your pet, or are shed into the environment. These eggs mature into larvae which are both persistent and resistant and  love to hide in carpet, bedding, furniture, etc. Adults will emerge weeks down the road and begin the life cycle again. As vets we often find live fleas or flea poo, little brown specks on the skin, on many pets when owners insist their pet does not have fleas. Fleas prefer moderate weather, however it takes several days of sub-freezing temperatures for the flea life cycle to be interrupted. This means that in a moderate climate like the UK, year round prevention is necessary. It’s also common for vets to recommend prevention year round regardless of weather because of other parasites that are also prevented by flea treatments, such as ticks. Due to their short life cycle, affinity for moderate temperatures and ability to persist in the environment – regular flea prevention is all the more important. 

Flea borne diseases

If you aren’t digusted enough already, unfortunately there’s more. Fleas can carry other diseases that can cause your pet (or you) to become ill. Historically, fleas have been the culprit to harbouring and spreading the bacterias guilty of causing plague and typhus in humans. Additionally, fleas are also the transmitter of the bacteria Bartonella, better known as cat scratch fever. Bartonella may cause infected cats to become unwell and can be spread to humans by a cat scratch. Mycoplasma haemophilus is another bacteria spread through fleas, and is a major concern for cats that spend time outdoors. This nasty bacteria can cause cats’ red blood cells to be recognised as foreign and destroyed, leading to potentially life threatening anaemia. Fleas also commonly carry the egg of the tapeworm Dipylidium, which if swallowed by your pet or humans will lead to development of the tapeworm along the intestinal tract.


When it comes down to it, not only are fleas annoying, they also pose a health risk to you and your pets. For this reason, vets encourage pet owners to be proactive in preventing fleas year round. There are many products on the market which can be overwhelming for owners. Which is right for your pet? Why are there so many? Why do I need a prescription when I can buy some over the counter? In general preventative treatments  containing a medication are going to be the most effective. Unfortunately “all natural products” will not achieve the results we desire in most cases. Not all products are created equal, and there is not one product on the market that prevents/treats all types of parasites. Make sure you consult a vet about which preventative is best for your pet to keep them parasite free.

VetBox subscriptions are tailored to your pet by our team of qualified vets and the treatments are sent automatically in the post each month. Fill out our quick online sign-up form to find the best treatment for your dog or cat. For pets with specific requirements, our vets can tailor their subscription even further so please get in touch to discuss. 

Dr. Kirsten Ronngren, DVM – MRCVS

Vet at VetBox