Fleas are everywhere, but not all the time, heartworms are everywhere almost all the time, and ticks are localized but present almost all year round.   So how do you know which combination flea preventative is right for you?

Advantage, Frontline, and Revolution all prevent fleas.  Advantage only prevents fleas, Frontline Plus prevents fleas as well as ticks, and Revolution prevents fleas and heartworms.

Advantage prevents against fleas and does not prevent ticks or heartworms.  For individuals living in well-groomed suburbs or apartments, Advantage is probably your best product.  If you have variations in flea seasons, you may be able to stop using Advantage during very cold months.  You will need to give your dog a separate heartworm preventative year round and begin using a product like Frontline if you decide to frequent wooded areas with your dog.

Advantagedoes have two combination products, K9 Advantix and Advantage multi.  K9 Advantix takes care of fleas and ticks but can be toxic to cats.  Advantage multi is a new product by Bayer, the makers of Advantage, that combines its flea preventative with heartworm preventative.

If you live in a wooded are frequented by deer and other wildlife (or if you and your dog enjoy hiking and camping), then you need a product that prevents ticks as well as fleas.  Frontline is probably your best choice.  You will need to give your dog a separate heartworm preventative throughout the year to prevent against heartworms, though.

Revolutionis a combination heartworm and flea preventative.  This product works well if you live in a warm climate where both mosquitoes (these little pests spread heartworms) and fleas are present all year long.  It also has the added benefit of preventing earmites.

For more ideas on choosing the best flea product for your dog, click here.

But how do they work?  And what do they kill?

All of these products are considered topical flea preventatives, which means they need to be applied to the skin of the dog in order to be effective. 

Advantage uses a nerve toxin (imidacloprid) to paralyze the flea, causing a relatively quick death.  According to Bayer, the maker of Advantage, this product starts killing fleas within minutes.  In my experience it usually takes between 24 and 48 hours to spread take effect all over the dog’s body.  Advantage is not toxic to dogs, only fleas.  Flea allergies in dogs results from the dog’s sensitivity to flea saliva.  Advantage is great for these animals since it paralyzes the flea’s mouthparts and prevents them from biting. 

Frontline Plus uses a dog’s sebaceous glands (skin oil glands) to spread and secrete the active ingredients, fipronil and methoprene, throughout the coat.  Although fleas don’t have to bite the dog in order for the poison to take effect, they have a tendency to bite prior to being affected by the active ingredients.  Ticks might also bite prior to absorbing the poison.  Because Frontline is spread through the skin’s oil glands, owners should refrain from bathing their dogs with soap (which strips the skin of oils) more than twice a month.  Like Advantage, Frontline Plus takes about 24 to 48 hours to become very effective. 

Revolution is absorbed through the bloodstream.  The flea preventative part of Revolution is absorbed into the tissues and affects the fleas through the skin of the dog.  The heartworm preventative in Revolution flows through the bloodstream in order to kill the microfilaria (heartworm larvae) that have been transmitted to the dog from a mosquito.  Since it works through the bloodstream, bathing is not as much of a concern with Revolution as it is with Advantage or Frontline .  As with the other products, Revolution takes between 24 and 48 hours to work.  According to the website, Revolution also kills American Dog Ticks.

It’s important to keep your dog on heartworm preventative all year round, especially in warm, humid areas of the country.

Keep your dog dry (no bathing or swimming) 48 hours before or after application.  Since some products require the dog’s skin oils to spread the product, he needs to replenish those oils prior to application. 

Remember to stay away from flea preventatives with pyrethrins since they have a tendency to cause toxic reactions in dogs and cats (neurological and physiological reactions)