Champlain Animal Hospital News
Heartworm Prevention in Dogs
It is spring again and our thoughts turn to protecting your dog from heartworm and parasite infection. Many different products are available to keep your companion safe. Each product is unique and we can help you determine which one is right for you and for your dog’s health and safety.
When to Start Giving Heartworm Preventive Each Year?
There is more to transmission than just mosquitoes; it must also be warm enough for a long enough time period to allow the development of infective microfilariae. In our region that time period is typically from mid-May until mid-October. Our recommendation, after a once yearly blood test is done to determine that your companion is free from heartworm infection, is to use the preventative from June 1 until November 1. If travelling south with your dog for the winter, then we suggest using the preventative all year long.
Ask us which product is the best choice for you and your dog!
Heartworm preventive medications are used to periodically kill larval heartworms that have managed to gain access to the dog’s body. The products available are intended for monthly use. This means each time they are given, they kill all the heartworm larvae that have accumulated in the past month. There are many topical and oral choices available in Canada.
Ivermectin-based Products:
HEARTGARD®, HEARTGARD PLUS® made by Merial
Preventive medication is given once a month. These medications use an extremely low dose of ivermectin that is adequate to kill any larval stages inhabiting the pet. The medication is given orally.
Other Parasites Covered
Ivermectin at the heartworm preventive dose is not strong enough to kill common intestinal parasites. Because of that, the dewormer pyrantel pamoate was added to cover hookworms and roundworms in the original Heartgard product. Whipworms are not covered by any of the ivermectin-containing products at this time. There are breed-related sensitivities with ivermectin as collie-related breeds have some difficulties.
Milbemycin Oxime-based Products
INTERCEPTOR® & SENTINEL® made by Novartis
TRIFEXIS® made by Elanco
These products are given orally once a month, clear microfilariae, act by killing all larvae accumulated in the month prior to administration, and will suppress female worm’s ability to reproduce.
Other Parasites Covered
The milbemycin products control roundworms, hookworms, and whipworms without the addition of a second parasiticide. Milbemycin can also be used in the treatment of demodectic mange. There are no breed-related sensitivities for milbemycin.
Selamectin-based Products:
Revolution made by Pfizer
Selamectin is a closely related cousin of ivermectin. It is designed for broad coverage of small animal parasites and will protect dogs not only against heartworm but also against ear mites, sarcoptic mange mites, ticks, and fleas. The product is topical and is applied monthly.
Moxidectin-based Products:
ADVANTAGE MULTI® made by Bayer
Moxidectin is another relative of ivermectin. Advantage Multi® is available for both dogs and cats as a topical applied monthly.
Advantage Multi® combines moxidectin with imidacloprid, the flea-killing ingredient in Advantage®, to create a broad spectrum anti-parasite product for both dogs and cats. Advantage® and Advantage Multi® are made by the same manufacturer (Bayer). Advantage Multi® prevents heartworm infection, kills roundworms, hookworms, and whipworms. The imidacloprid will kill fleas.
Courtesy of THE PET HEALTH LIBRARY by Dr. Wendy C. Brooks, VeterinaryPartner.com
