Flea Pills for Treatment and Prevention What to Use for Flea Prevention for Dogs and Cats

Flea Pills for Treatment and Prevention

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Flea prevention for dogs and cats should always be the first line of defense that pet parents take when going to war with the flea. In case prevention seemed to have failed you, there are pill form treatment options that can rid your pet of those pesky pests.

Fleas can use your pet as both a home and a source of sustenance. Find out how flea pills for dogs and cats work, and the pill treatment options that are available if prevention doesn't work.

Keep safety in mind: Always follow the directions when using medications, make sure to check the dosage for your pet's age and weight, and only give dog treatments to dogs and cat treatments to cats. To get the best results, treat all infested pets in the household so that fleas donโ€™t get passed back and forth.

Because orals generally treat either adults or eggs but not both, medications are often combined. Check with your veterinarian before combining medications.


Capstar comes in tablet form and can be given to cats or dogs to eliminate fleas. Give the medicine to your pet directly, or hide it within your pet's food. (Check to make sure that your pet has swallowed the pill.)

Before giving the tablet, weigh your cat or dog to determine the correct dosage, since it varies by weight. While kittens and puppies can also take Capstar, note that pets must be at least four weeks old, and weigh at least two pounds in order to take the drug. One dose of Capstar should kill all the adult fleas on your pet's body. If you still spot fleas, or if a re-infestation occurs, you can give your pet another dose. A separate medication is necessary to prevent eggs from hatching.

Capstar Summary

This treatment works on dogs and cats to kill adult fleas but does not kill eggs or fleas in other life stages.


Comfortis is both a treatment and a preventative for fleas on dogs over 14 weeks. Comfortis is not available for cats. Give Comfortis to dogs on its own as a treat, or within foodโ€”note that vomiting is a known side effect. As a treatment, Comfortis destroys adult fleas before they can lay eggs. Comfortis can also be used as a preventative, administered on a monthly basis.

Comfortis Summary

Comfortis treats and prevents fleas, but is only available for dogs. Comfortis requires a prescription.

Program Tablets

Suitable for both cats and dogs over four weeks old, Program attacks the flea's eggs and larva, but does not kill adult fleas. A separate medication is required to eradicate the adult population.

The program should be given to pets with their foodโ€”check to make sure your cat or dog has totally ingested the entire tablet. Give Program on a monthly basis, and check your pet's weight before administering, since dosage varies by weight.

Program Summary

This treatment can be given to both cats and dogs and prevents eggs from hatching.


A preventative medicine, Sentinel stops flea eggs from hatching, as well as guarding against heartworm. A different treatment is necessary to eradicate adult fleas. Sentinel is given on a monthly basis and is only suitable for dogs older than four weeks, and weighing more than two pounds. Sentinel can be given on a monthly basis and is a chewable tablet.

Sentinel Summary

This preventative treatment goes after flea eggs but does not kill adult fleas. It also prevents heartworm. Sentinel can only be used on dogs and requires a prescription.

Oral Flea Protection: Flea Pills for Dogs and Cats 

What is oral flea Protection?

Dealing with fleas on dogs can be a real ordeal. Oral flea protection refers to flea pills for dogs and cats you give to them to prevent fleas from harming them. While some topical flea and tick treatments, such as Frontline for cats and dogs or Revolution for dogs, could leave areas of your pet unprotected from harmful flea infestation, oral medications like Comfortis and Nexgard provide protection for your petโ€™s entire body. Some oral flea protection treatments begin working within thirty minutes, rendering all fleas dead within four hours. Because a female flea can produce as many as fifty eggs a day and five hundred eggs over a lifetime, it's critical to defend your furry friends against the aggressive reproduction of this harmful parasite.

Why use oral flea Protection treatments?

How do I know my pet needs flea treatment?

Signs of flea activity can be found in the fur of your pet. You may see flea dirt, which looks like small particles of soil but is actually waste generated by a meal of your pet's blood.

If your pet seems anxious or stops playing to scratch and bite, fleas may be the cause. If when examining the skin of your pet you find flea dirt or see live fleas, unfortunately, the situation won't improve without your action.

Many veterinarians recommend the use of oral flea protection medications in response to a sudden flea infestation. Oral flea protection treatments can provide visible results in less than an hour.

Fleas can transfer from pet to owner within ten minutes, causing itching and soreness. Hard, compact bodies make these dreadful parasites difficult to crush. If you find a live flea, the best way to dispatch the parasite is by drowning them in soapy water.

What are the differences between oral flea protection treatments?

Comfortis, which is available with a pet prescription from your veterinarian, comes in a chewable tablet and starts working in half an hour. If you have pesticide-sensitive pets or you just want to avoid topical treatments, this option may be for you. The best part is that you and your little buddy can battle fleas without a break in playtime.

  • The typical dosage is 13.5 mg per pound
  • Your pet should have a full stomach for maximum effect
  • One tablet prevents infestations for up to one month

Capstar is clean and easy. It comes in pill form, so you can feed it directly to your pet or mix it into food. This treatment is safe for pregnant pets and breeding animals, and safe for kittens more than four weeks old and over two pounds. Pet owners who choose this treatment report that they can see dead fleas falling off of their animals. Make note that this product is an immediate treatment for existing adult fleas and not a preventative.

  • Lasts up to 24 hours
  • Safe for younger animals
  • Kills all fleas within 4 hours

If your pet suffers from fleas, just getting rid of the current generation is not enough. Program Flea Killer for Cats is a preventative medication that interrupts the life cycle of fleas at every stage of growth, halting progress and ensuring death. Administer this medication as soon as flea season begins where you live to stop flea infestations before they begin. The dosage of this treatment is dependent upon your pet's weight and is administered just once a month.

  • Available in flavored tablets or in a liquid suspension
  • Administer on a full stomach
  • Comes in a six-month supply

Which oral Flea Protection is right for my pet?

  • Comfortis works instantly for pets 14 weeks and older and requires a prescription
  • Program Flea Killer is available in a six month supply
  • Capstar is safe for daily use with ongoing flea infestations

There are many different oral flea protection treatment options for pet owners. It's important to remember that medication engineered for dogs could be harmful to cats, and vice versa. The dosage levels in these products are important, so know the weight of your pet and consult your veterinarian before administering.

If an infestation is left untreated, pets could experience a lack of red blood cells or anemia. Animals may also contract tapeworms if they digest fleas carrying tapeworm larvae. Oral flea medication destroys fleas in every stage of life, leaving you and your pet free to enjoy one another's company without the pain and stress of crawling, biting pests.

What about pills for ticks?

Currently, there are no pills or oral medications available to prevent or treat ticks. The Preventic collar is, however, a nice add-on to a flea pill regimen for complete flea AND tick protection.

How PetPlus Can Help

If you are looking to protect your cat from fleas with oral medication, the PetPlus plan is the best way to get your cat's medication. Everything from Comfortis to Capstar can be purchased through PetPlus for an average saving of 33% off the retail price.

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This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis, or treatment by your veterinarian. Always seek the advice of your veterinarian or other qualified professionals with any questions you may have regarding a medical condition. Never disregard or delay seeking professional advice due to what you may have read on our website. 

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