How to Get Rid of Fleas


My cat has fleas and I have tried a bunch of products to try to get rid of the problem.  Any suggestions?


First, let’s briefly discuss the flea life cycle.  A single female flea can lay 20-40 eggs per day, and up to 2000 over her lifetime.  So when you see adult fleas, this is just the tip of the iceberg — roughly 5% of the problem!  The rest are eggs, which hatch into larva and then become pupa and finally an adult flea emerges.  When a flea bites your ankle, it has not jumped off your pet to do so.  Generally, the fleas on the pet are going to stay right where they are – on the perfect host.  The bite on your ankles is from the newly hatched flea, looking for a new dog or cat to jump on.

The eggs, larva, and pupa are usually found in highest concentrations in the areas where your pet spends most of its time (sleeping).  They prefer temperature in the range of 65-80 F and humidity of 75-85%.  The developing fleas often live in the carpet fibers of your floor, upholstery, pet beds, and other cracks and crevices in areas where your pet frequents.

In addition to being annoying to you and your pet, fleas can carry tapeworms, which commonly cause infections when the animal ingests fleas during self-grooming.

To get rid of the problem, you must break the life cycle at two points.  Kill the adult fleas (insecticide) and kill the eggs or larva (insect growth regulator or insecticide).  Currently the best products on the market for this are Advantage® (kills the adult fleas and larva),  Frontline Plus® (kills adult fleas and prevents eggs from hatching), Program® (prevents eggs from hatching), Capstar® (kills adult fleas), and Revolution® (kills adult fleas).   The most user-friendly topical products (Frontline Plus®, Advantage®, and Revolution®) tend to work for only about 3 weeks, and therefore need to be re-applied consistently every 3-4 weeks.  You should consult with your vet first before using these products more than once a month (“extra-label” use).

Save your money when it comes to over-the-counter flea collars, dips, powders, most sprays, and pyrethrin based spot-on products.  They just don’t work.  Fleas are very resistant to these products today.  The only exceptions are the insect growth regulator sprays, which do stop the flea eggs from hatching when used according to the label directions.

Advantage®, Revolution®, and Frontline® are vet products and are only guaranteed when purchased from a veterinarian.  There have been reports of counterfeit products and product failures in some instances when purchased from non-vet suppliers.

When undertaking proper flea control, every pet in the vicinity must be treated consistently, even if you don’t see fleas on every pet.  Remember, don’t stop treating when you are no longer seeing adult fleas – we still need to get rid of the eggs, larva and pupa.  Most premise infestations take 5-6 months of consistent treatment to control, and may require life-long measures if your pet goes outside.  In this part of California, fleas are a year-round problem.


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Max Conn, DVM is the owner of Cat & Exotic Care of the CentralCoast, a full service veterinary hospital dedicated to the special needs of cats, birds, reptiles and small mammals.  Cat & Exotic Care is located in PismoCoastPlaza, 565 Five Cities Drive, 805-773-0228.  More information can be found at


Disclaimer: The informational handouts and website links above are for informational purposes only, they are not intended to replace veterinary care.