Anti-Flea Medications

Oral medications are best for ongoing flea control

Oral flea medications are an alternative for pet owners who are wary about putting chemical pesticides on their pet's skin. The National Resources Defense Council (NRDC) gives oral flea treatments a lower risk level than topical flea treatments. The group especially cautions against using topical treatments around young children and pregnant women.

On the whole, veterinarians recommend oral medications for pets that are chronically susceptible to flea infestations or that are constantly exposed to flea-infested environments. Novartis has cornered the market for oral flea medications with brands like Capstar, Sentinel and Program. These products either kill adult fleas or break the flea's life cycle, but not both, so you need to buy two for complete protection.

Capstar for Dogs (*Est. $30 for six doses) and Capstar for Cats (*Est. $30 for six doses) are recommended more often by experts and pet owners as a way to quickly kill adult fleas on both dogs and cats. No prescription is needed for this oral pill, which can be given as often as daily until fleas disappear (all other topical and oral products should not be repeated until a month has passed). The manufacturer claims 90 percent of adult fleas will be killed within four hours for dogs and six hours for cats. Capstar is safe to use on puppies and kittens as young as four weeks old, as long as they weigh at least 2 pounds. No other product is approved for cats younger than six weeks old.

While we didn't find as many pet-owner reviews online for oral medications as topical flea treatments, some still receive plenty of feedback. Capstar is among those that do, and much of that feedback is positive at sites like 1800PetMeds.com. Owners say it works extremely fast and that they like not having to deal with the hassle and mess of trying to apply a topical treatment. Many owners say it's "amazing" how the fleas fall off.

If your dog just won't swallow a pill (no matter what tasty treat you hide it in), you might try Comfortis (*Est. $90 for six-month supply) which is a beef-flavored chewable tablet. (Comfortis isn't available for cats.) This medication is only administered once a month, but the online price is three times as much as Capstar. Comfortis requires a prescription and cannot be used for puppies less than 14 weeks old, which is the oldest age restriction of any flea treatment in this report. According to the manufacturer, the most common side effect of Comfortis is vomiting.

The main downside of Capstar and Comfortis is that they don't have a residual effect -- meaning more fleas can crawl onto the cat or dog -- and they don't kill eggs or larvae. Using another medication with an insect growth regulator (IGR) may be necessary to completely eliminate fleas; these medications cause the animal's skin to secrete a substance that inhibits the development of flea eggs and larvae, thus interrupting this pest's life cycle.

Program Flavor Tabs for Dogs (*Est. $55 for a six-month supply), Program Flavor Tabs for Cats (*Est. $55 for six-month supply) and Program Suspension for Cats (*Est. $60 for six-month supply) contain the IGR luferuron, which is safe to use on animals as young as six weeks old. However, owners writing at 1800PetMeds.com give Program only a so-so rating, though some of the less pleased owners seem unaware that Program isn't intended to kill adult fleas. Other reviewers say it works well and is ideal for pets that have reactions to topical flea treatments. Program is also available in a 12-dose package. If your cat isn't agreeable about taking liquid medication or chewable tablets, you can also ask your vet to administer Program in a single injection that is good for six months.

If you don't mind getting a prescription first, Sentinel Flavor Tabs (*Est. $75 for a six-month supply) is another option for killing flea eggs and larvae on dogs. Sentinel contains the same active flea control ingredient as Program, but adds a chemical that controls heartworm, hookworm, roundworm and whipworm. This is similar to the topical treatment Revolution, but without the tick control. Sentinel is safe to use on puppies as young as 4 weeks old and is also available in a package with a 12-month supply.

Main Street Pet Care vet Ben Leavens recommends Sentinel Flavor Tabs above other flea control options for dogs. However, veterinarians at PlacervilleVet.com say this flea birth control isn't as effective as topical treatments that also kill adult fleas. Sentinel draws good user reactions at 1800PetMeds.com, though feedback isn't as extensive as for some other flea control products. Still, those that do comment say that their pets are free of fleas and experience no negative side effects from Sentinel.