Flea and Heartworm Prevention

December 18, 2011

Decisions decisions. What type of flea and heartworm treatment should your dog use? Unfortunately the more that is researched, the scarier the medications may sound. As with human medications, you always have to determine if the problem outweighs the possible side effects.  Side effects may be rare but they can happen.  Being a responsible dog owner means educating yourself about the drugs you give your dog.

Sentinel = Program + Interceptor
All in one monthly pill for the prevention of fleas and parasites (heartworm, roundworm, hookworm, whipworm but not tapeworm)

Pros – Monthly tablet to administer for both flea and heartworm prevention
Cons – Does not kill fleas on contact. It is a flea birth control, which prevents infestations. If you do find adult fleas you would have to treat them manually (bath, spray the yard, etc) or use an emergency type remedy such as Capstar. Side effects include itchy skin, hives, vomiting, diarrhea, lethargy, convultions.  Does not control ticks.
Active ingredient: Lufenuron, an insect development inhibitor

Pros – Prevents heart worms, has been around since 1995. Monthly chewable tablet, also controls hookworms, roundworms and whipworms (but not tapeworms)
Cons – Side effects listed include:  depression, lack of energy, lack of coordination, excessive drooling, loss of muscle strength, and sometimes seizures. Does not control tapeworms
Active ingredient:  Milbemycin Oxime.

Trifexis = Comfortis + Interceptor
Trifexis is a new oral pill that came out in 2011 which covers a wide variety of worms and fleas. It contains Comfortis – which is a flea killer and Interceptor – a well known heart worm preventative.

Pros – Kills adult fleas, monthly chewable tablet
Cons – Side effects reported including seizures and death. There is an official FDA warning not to administer Comfortis with Ivermectin. Does not control ticks.
Active ingredient: Spinosad is a member of the spinosyns class of insecticides, which are non-antibacterial tetracyclic macrolides. It works by attacking the nervous system of insects, causing rapid death of adult fleas.

Already mentioned above.

FDA-approved monthly medication available only through a veterinarian – and is NOT a pesticide registered by the EPA used to treat fleas and parasites.
Pros:  Controls fleas, heartworm, ear mites, sarcopic mange, American dog ticks
Cons: Topical application could sometimes be messy. Does not control whipworms, roundworms, tapeworms, or hookworms. Side effects include drooling, diarrhea, hair loss at medication site, vomiting, and incoordination
Active ingredient:   Selamectin, which interferes with the parasite’s nervous system.

 Advantage Multi
Pros: Monthly treatment of heartworms, roundworms, hookworms, whipworms and fleas.
Cons: Topical treatments can be messy. Does not control ticks or tapeworms. Toxic to cats and should be kept away from children. Side effects include medicinal odor, hyperactivity, lethargy, itchy skin.
Active ingredient:  Imidacloprid acts on the nervous system of the flea to cause paralysis and subsequent death. Moxidectin acts on the nervous system of heart and intestinal worms to cause paralysis and subsequent death.

Heartguard/Heartguard Plus
Pros: Monthly chewable heartworm prevention pill. Also controls roundworm and hookworms.
Cons: Not recommended for Collie, Shepherd herding breeds as they are reported to have adverse reaction with Ivermectin (elevated dosages can cause mydriasis, depression, tremors, drooling, excitability, stupor, coma and death). Does not control whipworms or tapeworms.
Active ingredient:  Ivermectin. The plus version includes Pyrantel

Pros: Begins to work within 30 minutes to kill adult fleas. Easy to administer tablet. The company claims the product is safe to use daily as needed.
Cons:  Does not control flea eggs or larvae. Does not control ticks. Temporary solution, only effective for a day.
Active ingredient: Nitenpyram belongs to the chemical class of drugs called neonicotinoids, which interferes with nerve transmission in fleas

Frontline Plus
Monthly topical treatment to prevent fleas and ticks.
Pros: Controls fleas and ticks. Products have been around for a long time.
Cons: Topical treatments can be messy. Side effects include hair loss or irritation at site. There are some reports that Frontline does not always work or loses effectiveness with time.
Active ingredient:  Fipronil is stored in the oil glands under your pet’s skin. It is then distributed continuously to the skin and hair of your pet through the hair follicles.

Advantage/Advantage II
Pros:  Monthly topical flea control
Cons: Does not control ticks
Active ingredient:  Imidacloprid acts on the nervous system of the flea to cause paralysis and subsequent death.  Side effects include site irritation, lethargy, medicinal odor.

K9 Advantix
Pros: Monthly topical treatment to control fleas, ticks, mosquitoes, flies, lice. Waterproof.
Cons:  Side effects include neurological symptoms, hyperactivity, itchiness, paralysis in hind quarters, hives, seizures. Toxic to cats.
Active ingredient:  Imidacloprid and permethrin attack the parasites’ nerve cells at different sites. Pyriproxyfen, an insect growth regulator, affects the early flea stages to prevent development of the flea

Injectables such as Proheart should probably be avoided as there were numerous reports of side effects and death. These medications are essentially pesticides and poisons, which is how they kill the fleas and worms. There aren’t many holistic or natural cures so limiting the dog’s exposure to the medicines is keen. It might be a good idea in some areas that are much colder to skip the flea and heart worm treatment during the winter months. Of course, your mileage may vary.

Quick tip: I’ve read in several websites that using some of the heartworm preventatives such as Heartgard Plus ever45 days instead of 30 may be just as effective. Please google at your discretion!


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