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Fleas (Ctenocephalides felis) are the most common external parasites found on cats in North America. Not only are these bugs irritating to your cat, they can also pass on other parasites such as tapeworms or lead to anemia and skin allergies. They may also transmit several serious bacterial infections to your cat and ultimately to you, such as Cat Scratch Fever (Bartonella) and the Plague (Yersinia pestis).

Why Is It so Difficult to Get Rid of Fleas? 

Once a female flea finds a suitable host (such as your cat), she can lay up to 50 eggs per day. In addition, the immature life stages of the flea (eggs, larvae and pupae) can persist in the environment for a couple of weeks to several months. Some of these life stages are difficult to kill, and they comprise up to 95% of the flea population at any given time.

Many people mistakenly think that when it is cold outside, all fleas will die. They may die in some colder areas of the country or (more likely) become dormant outside, but fleas that are inside your home live quite comfortably during the winter. Additionally, it is impossible to get rid of the fleas that live on wild animals around your home that can ultimately reinfest your pet.

Fortunately, many good flea products are available today that effectively remove fleas from your cat and your home. Here are a few important things to remember before using these products:

  1. You must use the right product at the right time for the right length of time. You cannot expect one dose of a medication to do the trick. Flea eradication will require several months of continuous treatment.

  2. Never use products on cats that are labeled for dogs only.  Some chemicals (e.g., permethrins) are not safe to use on cats. Only use the correct dose of a feline product on your cat.

  3. If you have any questions, talk to your veterinarian about how to treat your cat safely and effectively.


How Can I Kill Fleas on My Cat?

Several factors must be considered before deciding which type of flea treatment for cats will work best in a given situation, including effectiveness, safety, cost, potential side effects, and formulation.

The most effective flea control products will contain an adulticide (a product that kills adult fleas before they can lay eggs) or an insect growth regulator (IGR) that sterilizes flea eggs and prevents the immature fleas from growing up and reproducing.


Topical Cat Flea Treatments


Spot-on cat flea treatments contain a small amount of liquid that is applied to your cat’s skin once a month.  Many claim to be waterproof, but if the medication resides in the skin, frequent bathing can reduce their effectiveness. They may also be rubbed or groomed off when wet, so it is best to keep an eye on your cat and avoid petting them until the liquid dries. 

Sprays, Dips and Shampoos

Once a major part of flea-control programs, sprays, dips and cat flea shampoos only work at killing fleas on the cat at the time of application, but do almost nothing for the hatchling fleas coming from the environment post-treatment. Many different products are available, so it is important to make sure the one you use is safe for cats.

Cat Flea Collars

A cat flea collar can be an attractive option for some pet owners. They are easy to use and typically have few side effects.  However, old-style flea collars may not be very effective, especially in areas of the body farthest from the collar. Some of the newer products cost more but have data to support better efficacy.

Oral Flea Medicine for Cats

Oral flea medicine for cats have several advantages:

  • They do not leave behind any chemical residues
  • They have consistent efficacy across the skin

Injectable Flea Control

Another option for flea control is a 6-month injection given by a veterinarian. The active ingredient (lufenuron) prevents flea eggs and larvae from developing.  Since it does not kill adult fleas that may hop on your cat and bite, it is not a good choice for flea allergic cats or if it is your goal to never see adult fleas on your cat. It can prevent infestations from developing, however.


Ancillary Flea Treatments for Cats

While treating your cat with an effective flea product is most important, there are several other ways to speed up the elimination of fleas from your pet and home:

  • Vacuum your carpets and sweep your floors regularly to remove flea eggs, larvae and pupae.  Remember that 95% of the flea life cycle is spent off your pet! Just make sure to empty or discard your vacuum cleaner bag each time you use it.
  • Treat all cats and dogs in your home.
  • Wash all bedding in hot water.
  • Treat your house and yard or hire a professional exterminator.
Data Source: 2016 

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