External parasites prevention for dogs

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You can never be too vigilant when it comes to fleas, ticks, lice, and mosquitoes attacking your dog and yourself on a sunny spring afternoon. With many preventative products on the market, it can be confusing for pet owners to choose what the best product for their dog is. Few of the many factors to consider when choosing a product are:

  • Dog’s age
  • Waterproof/water-resistant product
  • Which parasites are killed and repelled
  • Treatment or treatment/preventative
  • Type of application
  • How fast the product starts working
  • How long the product remains active
  • Your dog’s lifestyle and risk factors
  • Price

To make this a bit easier for you, we will review some of the most popular flea and tick medications on the market divided into categories based on the way of application and administration. These include drops, pills, collars, and sprays.

Drops or spot-on treatment is probably the most popular method of preventing and treating flea and tick infestation. The compound kills the parasites through contact, meaning they do not have to bite the dog first. This reduces the risks associated primarily with tick-borne diseases.

Frontline Plus for dogs

Frontline Plus drops contain Fipronil and S-methoprene and can only be applied on dogs older than 8 weeks. The ingredients start killing fleas, tick, and lice very fast and the dog is clean within 12 hours after application. The waterproof characteristics are suitable for dogs that tend to get wet. Additionally, Frontline Plus kills flea eggs and larvae. If the dog spends a lot of time in nature or playing with other dogs the treatment should be repeated monthly. When you apply Frontline Plus you just need to snap off the seal and squeeze the solution through the long and narrow tip leaving no mess behind. The product has a strong chemical odor compared to similar products.

K9 Advantix II for dogs

Besides fleas, ticks, and lice, K9 Advantix II spectrum covers mosquitoes and biting flies at all life-stages. It can be applied on puppies older than 7 weeks of age. After the spot-on application, the activity starts within 12 hours and lasts for up to 30 days. The treatment is monthly. The product includes 3 active ingredients: Permethrin, Imidacloprid, and Pyriproxyfen. In our opinion, K9 Advantix II will be most helpful for dogs living or traveling to places where Leishmaniasis is confirmed. More active ingredients mean a higher possibility for side-effects and drug interaction so consult your vet when in doubt.

Advantage II Dogs

With Pyriproxyfen as the only active ingredient in the product, Advantage II has a narrow killing spectrum. The topical treatment successfully kills fleas at any life-stage and tends to be effective for the treatment of lice infestations. Just like the previous products, Advantage II protects the dog for 30 days and the treatment should be repeated monthly. Its waterproof properties mean the furry friend can take a dip soon after application. If your dog isn’t at high risk of encountering ticks and doesn’t spend much time in nature the product you should consider this product.  

Pet Armor Dogs

Pet Armor is considered to be one of the more pocket-friendly options when it comes to flea and tick treatment in dogs. Flea eggs and larvae remain intact after application, while mosquitoes are repelled by it. It’s waterproof and can be used in dogs older than 8 weeks of age. Sometimes it may cause skin irritation at the application site and it’s not advised to be used in dogs with a history of seizures. An interesting fact is that the product aids in the control of scabies mange mites. The only active ingredient stated on the label is Fipronil. We think it’s safer to use a product with more active ingredients if your dog lives an active outdoor life. PetArmor is almost odorless and the fleas start dying 12 hours after application.    

Sentry Fiproguard Dogs

Sentry Fiproguard is recommended for dogs that are at low risk of frequent flea and tick infestation. The solution contains only Fipronil so it has a rather narrow killing spectrum. It’s waterproof and you can give your dog a bath at least 24 hours after topical application of Sentry Fiproguard. Chewing lice are also sensitive to the product. The protective seal needs to be cut open in order to apply the solution and it can get a bit messy due to the wider tip.  

Sentry Fiproguard Plus Dogs

Both active ingredients combined, Fipronil and S-methoprene are successful at killing adult fleas, flea eggs and larvae, chewing lice and ticks. Frontline Plus is made of the same ingredients however Sentry is considered as the more budget-friendly product. The activity starts 12 hours after application and continues for 12 weeks. Sentry Fiproguard Plus is effective against ticks for 4 weeks only. You can apply it on puppies older than 8 weeks of age. The product is waterproof and should be repeated monthly when there is a high risk of tick infestation. Just like PetArmor and Sentry Fiproguard, it leaves almost no odor and if both you and your dog have a sensitive smell you can opt for this product.    

Oral medications

Some dog owners prefer pills instead of spot-on solutions. They are available as tablet or chewables. Once ingested the medication gets to the dog’s bloodstream and circulates through the body for some time. The active ingredients kill the bloodsucking parasites such as fleas, ticks or mosquitoes when they are feeding of the dog. Existing flea infestations can be solved with treatment products killing adult forms. Usually, these types of products don’t offer long-term protection. There are some that offer long-term protection and can be used both for treatment and prevention of infestations. When you want to combine oral and topical external parasite treatment always consult with your veterinarian first.

Advantus Soft Chews for dogs

The product uses the insecticide Imidacloprid to quickly eradicate the dog’s flea infestation. Is really powerful and manages to kill more than 95% of fleas within an hour of administration. The best part about Advantus Soft Chews is that your dog will actually like them. The medication smells and looks like regular dog treats so most of the dogs will enjoy taking it. They act for a day so there isn’t a long-term protection.

Capstar for dogs

Capstar is another flea medication containing nitenpyram as the only active ingredient. It’s pretty safe to use and can be given to dogs older than 4 weeks. After administration, more than 95% of fleas are killed within 6 hours. Capstar is the same class of flea treatment like Sentry CapGuard and PetArmor FastCaps meaning it’s a bit difficult to give and the effect only lasts for 24 hours.  


Some people might imagine flea collars as old school, but in fact, new innovations in design made them quite potent products. The new designs are thin, effective, adjustable and most importantly almost odorless. They contain active ingredients that kill and/or repel fleas and ticks delivered almost immediately after you easily put them on the dog’s neck. Although they are not recommended as a genuine treatment for existing flea infestations they aid in killing some of the fleas.       

Seresto for dogs

Except from adult fleas, flea larvae, flea eggs and ticks, Seresto protects the dog from sarcoptic mange as well. It contains two active ingredients, Flumethrin and Imidacloprid, it isn’t greasy and it’s completely odorless. For added visibility, during the night the collar features light reflectors. Existing fleas and ticks are killed within 24 hours of application, and 24 hours later the preventative mechanism is fully active. Puppies as young as 7 weeks of age can wear the collar. Seresto keeps its repellent activity for an amazing 8 months. Some dogs may exhibit signs of local irritation at the site of application of the collar in which case you should consult a veterinarian immediately.

Flea Sprays

Using flea sprays is probably the most inexpensive way of treating active flea infestations. They are convenient to use and you just need to spray the whole coat of the dog. You must be careful and avoid spraying the content too close to your dog’s eyes and mouth. Some of the sprays can also be used for your home if you suspect there is a nasty flea nest.

Vet’s Best

The solution for topical treatment doesn’t contain any harsh chemicals and can be used on the dog’s coat and indoor surfaces. As long as it goes for immediate treatment of flea infestations the product will show results, but prolonged preventative is highly unlikely. Vet’s Best also has some anti-tick properties and can be used on puppies older than 12 weeks of age.


The active ingredients Permethrin and Pyriproxyfen kill fleas in all life-cycle stages and tick. Pyriproxyfen is an IGR (Insect Growth Regulator) and stops flea eggs from hatching. With that in mind, we can say SentryHome provides some sort on long-term protection. In addition to the insecticidal properties, the product offers deodorizing technology keeping furniture, carpets and your dog’s bedding free of odors.

Flea and tick shampoos

Flea and tick shampoos are used the same way other bath products are used. These products kill adult fleas and wash away eggs, allergens and flea waste off the dog’s coat. After applying them on the wet coat within a few minutes you need to rinse thoroughly with warm water.

At last, the product you are about to choose depends on your personal experience with different flea and tick products. If you are still not sure, imagine how your dog would react. Will it be easier to give him a bath or pill? Does he require monthly topical preventative or just a single flea treatment? Have you ever noticed allergic reactions to some products? Whenever in doubt feel free to contact your veterinarian and consult what the best option for you and your dog might be.       

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