External parasites prevention for cats

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Indoor cats are considerably less prone to flea infestations compared to dogs because they rarely leave the premises of their households. However, that does NOT mean that indoor cats can’t get fleas and other external parasites. Cats living both outdoor and indoor lives are at high risk of getting flea-infested. Checking your cat’s coat regularly is important. Whenever you notice dirty specks in the fur and frequent scratching the problem might be fleas. Remember that excessive itching and other skin condition aren’t always a result of flea infestations and veterinary check-ups are always a top priority.

Many external parasites, especially fleas colonize and reproduce rapidly. Owners must react even faster to solve the problem and prevent nesting inside the home. There are many products on the market so choose wisely according to the:

  • Cat’s age
  • Cat’s lifestyle
  • Cat’s sensitivity to active ingredients
  • Type of application of the product
  • The necessity to treat or treat and prevent
  • Time of action
  • Price of the product  

We will review some of the most popular external parasite medications for cats on the market. To make it a bit easier for you we divided the products on the way of application and administration.

Topical or spot-on treatment in the form of drops is the most popular treatment for fleas and other external parasites in cats. The medication is applied at the base of the neck where the cat can’t lick it. Spreading throughout the body the solution kills the insects on contact and usually prevents reinfestations for a prolonged period of time. Never use products for dogs on cats as they can cause serious health issues in your cat!

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Frontline Plus for Cats

Frontline Plus for cats uses Fipronil and S-methoprene as active ingredients to kill fleas. The product breaks the insect’s life-cycle by destroying flea eggs and larvae and it’s also effective in killing ticks. It can be applied on cats and kittens weighing over 1.5 lbs. The solution is waterproof and protects the animal from getting reinfested for 30 days. The peak insecticide activity is achieved 16 hours after application. This might be the best long-term preventative solution for cats that frequently go outdoors and tolerate the medication well.

Advantage II for Cats

While Advantage for Cats mainly kills adult fleas, Advantage II uses Imidacloprid and Pyriproxyfen combined to target the insect’s life-cycle by killing eggs and larvae as well. The product works through contact so the fleas don’t have to bite the cat in order to die. It’s easy to apply, fragrance-free and starts working 12 hours after applying. If your cat doesn’t need immediate relief and you want to achieve long-term protection (at least 30 days) you might consider using Advantage II. Cats should be dry prior to application and the product cannot be used in kittens younger than 8 weeks of age.

Cheristin for Cats

Cheristin for cats is a fast-acting topical product with Spinetoram as the main active ingredient. The insecticidal effect takes place 30 minutes after applying and within 12 hours more than 98% of fleas are eradicated. It’s easy to apply and can only be used in cats older than 8 weeks of age. Some side-effects may include hair loss and redness on the application site, inactivity, vomiting, and loss of appetite. In our opinion, Cheristin is a good option when we want to achieve fast-relief from flea infestations in cats that tolerate the product well. Monthly application is required for long-term prevention of infestations.

PetArmor Plus for Cats

PetArmor Plus for cats contains two active ingredients Fipronil and S-methoprene, same as Frontline Plus. It can be applied to cats older than 8 weeks of age. The product is waterproof and once applied starts killing fleas in all life stages within 6-12 hours. PetArmor Plus is also effective against chewing lice and ticks. The treatment should be repeated monthly to achieve long-term protection.

Vectra for Cats

Vectra has two active ingredients that work separately. Dinotefuran kills adult fleas quickly via contact meaning that the insects don’t need to bite the cat in order to die. Pyriproxyfen prevents the development of flea larvae and eggs contributing to long-term protection. The solution is non-greasy, quick drying and easy to apply. Adult fleas start dying 6 hours after application. Kittens under 8 weeks of age shouldn’t be treated with Vectra for Cats.

Sentry Fiproguard Plus for Cats

Fipronil and S-methoprene are the two active ingredients effective in protecting the cat from flea infestations for up to 12 weeks. The solution kills adult fleas, chewing lice and ticks and breaks the flea life cycle by killing flea larvae and eggs. The product is waterproof and can be used on cats older than 8 weeks of age weighing 1.5 lbs or more. Maximum effect is achieved 12 hours after application.

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Oral medications

Oral medications are the second most popular treatment option when it comes to dealing with cat’s external parasites issues. Cats sensitive to topical solutions might be better off with oral treatment that proved to be a safer option for them. There are two types or oral flea and other external parasite medications – for daily use and for prolonged prevention of infestations. Once ingested, the active ingredients transfer to the cat’s bloodstream and circulate for some period of time. Fleas and other external parasites are killed when they penetrate the animal’s skin and attach to capillaries.


Capstar oral tablets have similar properties as the previous two as they contain the same active ingredient. The tablets start working within 30 minutes after ingestion and more than 90% of adult fleas are dead after 6 hours. You can give the tablets to kittens older than 4 weeks of age. As a result of the fleas dying, your cat may experience excessive scratching while the activity lasts (24 hours).

Flea collars

Flea collars for cats are a great alternative to topical and oral medications. They are long lasting and almost odorless. The active ingredients are slowly released into the skin and hair for a longer period of time, killing ticks, fleas and other external parasites on contact.

Seresto for Cats

The dual-action (Flumethrin; Imidacloprid) protective collar kills and repels fleas and ticks for 8 consecutive months. That means that you will achieve long-term protection for your cat from diseases transmittable through external parasites. The existing fleas are dead within 24 hours after the collar is applied. Tick infestations are managed after 48 hours and reinfestations are blocked for the next 8 months. Seresto also kills chewing lice, but only for a month after application. The product can be used as a long-term treatment plan for sarcoptic mange. The collar is odorless, not greasy and water resistant. The safety mechanism prevents strangulation and doesn’t cause harm if the cat chews on it. Seresto can be put on cats older than 10 weeks of age.

Flea Shampoos and Sprays

You can opt for flea shampoos if your cat doesn’t really mind taking a bath once in a while. Some of the shampoos are great because they are a quick solution and prevent reinfestations for a month. Sprays on the other hand are very useful when you want to eradicate fleas in your household.

Advantage Shampoo & Advantage Spray

Advantage Shampoo is a multi-component product used for killing fleas and ticks in cats. It can be used in animals older than 12 weeks of age. The treatment with the product can be repeated after 7 days. In addition to treating your pets, you can also opt for Advantage spray and clean your household and the surrounding environment to achieve a complete flea control program. The spray can also be used on the animal when the cat is older than 7 months of age.

Different owners have different opinions on and experiences with the products. Some prefer spot-on treatment and others opt for long-term repellent collars. There isn’t a single factor that will determine what the best option for your cat is, so you might try a few of the products until you find the perfect fit. You can always consult with your veterinarian and get a professional opinion on which external parasite treatment suits your cat’s lifestyle the best.

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