Written By : M Samy

What flea medicine works best for cats?

The flea medicine that works best for cats is the one that contains an IGR (insect growth regulator); This active agent will attack fleas at every stage of their development, preventing the eggs from hatching and rendering the larvae sterile, which will stop the spread of the infestation. 

If you want to get rid of your cat’s fleas quickly and effectively (read the article for the step-by-step method), you’ll need to follow a well-defined method, the steps of which I’ve explained in this article.

I’ve already talked about the best cat flea treatments that don’t need a vet prescription, here they are now; the list of the most known cat flea treatments, their advantages, and disadvantages:

What flea medicine works best for cats?

1- Most effective Topical cat flea medicine


Advantage 2 contains an Insect growth regulator, the ideal solution to break your cat’s fleas life cycle, in fact, these IGRs like Imidacloprid prevent eggs from hatching and flea larvae from becoming adult fleas in addition to that, it has other components that keep your cat free from fleas, eggs, and flea larvae.

I highly recommend you this product. As you know, fleas can be fatal for cats, especially if they’re already weakened by illness. That’s why it’s important to treat them against fleas even in winter and cold areas and continue with preventive treatments to reduce the risk of infestation as much as possible.

Frontline Plus 

Frontline plus, this cat flea medicine, works really fast, eliminating fleas and also ticks. this flea treatment contains a compound called Fipronil, which once absorbed by the fat of your cat’s skin, becomes waterproof and will therefore remain effective for longer.

But you shouldn’t bathe your cat two days before and two days after applying Frontline Plus or any other topical flea treatment.


Revolution is the third spot-on flea medicine I recommend to quickly get rid of fleas on your cat. This cat flea medicine contains a molecule called Selamectin and other active agents such as Sarolaner.

Revolution is also highly effective not only for ridding your cat of fleas but will protect your cat against ticks, heartworms, intestinal parasites, and finally some ear and skin mites.

As you know there’re a lot of ways, even your indoor cat can get fleas, but this product is especially recommended for outdoor cats, cat that love passing a lot of time out; especially when you live in a relatively warm and humid climate, which is highly conducive to flea infestations.


Cat owners also seem to like this product, which has Fluralaner as its active ingredient. According to its manufacturer, Bravecto will protect your cat longer than other topical flea medicines. This treatment is reapplied every 12 weeks and if necessary every two months during flea season for outdoor cats.

Bravecto is not recommended for cats under 6 months of age or weighing less than 2.6 lbs.

2- Best cat Oral Flea medicine (Tablets)


Oral flea Medications like CAPSTAR don’t last more than 48 hours, they’re safe to use even for cats over 3.5 pounds and they start working after just 30 minutes.

On the other hand, you have another good Oral cat flea medicine called Sentinel, an insect growth regulator, also recommended by vets for its ability to protect your cat from fleas and heartworms for almost a month. Sentinel will prevent flea eggs from hatching and their larvae from becoming adults and laying eggs in turn.

The problem with these oral tablets is that they don’t protect your cat from adult fleas, which may jump on your cat and feed on its blood, but their eggs won’t hatch.


Trifexis, on the other hand, will start killing adult fleas just 4 hours after your cat has been treated, and its effect lasts for almost a month. This product can also be combined with a spot-on treatment like Frontline for severe infections.

3- Flea Collars

Flea collars are not recommended, I personally don’t recommend them because they are only effective locally, i.e., flea collars will only protect your cat’s neck area from fleas, and fleas will simply continue to live quietly on your cat’s back belly, and paws.

Cat flea collars also don’t have a lot of residual activity and unlike previous flea treatments which can protect your cat for over a month, flea collars effect only last one to two weeks maximum.

Flea collars can also have some bad side effects, and become toxic to your cat and especially to your children if they touch them and put their fingers in their mouths immediately afterward. 

Most of the time, the product released by these flea collars remains on your cat’s hair and will quickly end up on your hands when you stroke your cat.

But if you think a flea collar is the best way to protect your cat from fleas, I’d advise you to buy SERESTO or ULTRAGUARD Pro; the original brand, but keep monitoring your cat’s behavior and watch out for any changes or symptoms for at least a week or two.

4- Flea Shampoos

The one I recommend is Advantage Flea shampoo

Flea shampoos are recommended only when your cat is severely infested with fleas, and will kill the fleas almost immediately.

I don’t recommend using these flea shampoos as a basic treatment for getting rid of your cat’s fleas, because they only protect your cat for one or two days, and it’s very difficult to prevent your cat from licking itself and absorbing a little of the product, which could cause some bad side effects.

I strongly advise against using this kind of flea medicine on a kitten, as for any other chemical cat flea treatment, a good daily brushing and a bath with just water would be enough to remove fleas from your kitten. There’re some natural ways to protect your cat from fleas as well.

If you notice that your cat has a lot of fleas on him, you can give him a bath with a flea shampoo, wait two or three days and then treat him with an on-spot flea medicine that will last for almost a month.

Final Thoughts

Finally, when it comes to protecting your cat against fleas, for me, I think Advantage 2 is the one that seems best, but everything will also depend on you and your cat. You’ll also need to keep giving your cat preventive flea treatments, sanitize your whole house and backyard, and vacuum frequently to prevent fleas from finding their way back onto your cat’s back.

M Samy pet blogger and author at famillypet

About Author

Hey! Samy here , Welcome to my Blog I'm an animal lover, especially pets and Really concerned about their well being ; I've been around and caring for all my life and Now ; a full-time Pet blogger at your service . My motto here at Famillypet is: "Pets First" ... Read More