How do I Choose the Best Dog Heartworm Preventative?

Preserve your dog's outdoor enjoyment by protecting him against heartworm disease.
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Heartworms circulate through your dog’s bloodstream to take up residence in his heart and lungs, leading to lung disease, heart failure and death. Treatment for heartworm disease, which is transmitted by mosquitoes, is more difficult and much more costly than prevention. Several heartworm preventative products exist to protect your furry friend from this dreaded condition. Your veterinarian determines which formulation is best suited to your dog’s needs.

Deciding Factors

When deciding which heartworm preventative is right for your dog, your veterinarian considers such factors as your dog’s weight, age and breed, as well as your economic needs, your geographical location and your ability to give your dog the medication. Most heartworm preventatives include added protection against other parasites, such as intestinal parasites or fleas, and exist in oral, topical and injectable forms. Your vet also considers the dog’s medical history, especially if your dog has drug allergies.

Monthly Management by Mouth

Your dog counts on you to administer his oral heartworm preventative each month. Many dogs accept the chewable oral tablets as readily as their treats. Many products containing ivermectin as the heartworm preventative ingredient also offer protection against roundworms and hookworms. Certain breeds, including collies, border collies, Shelties, English sheepdogs and Australian shepherds, are predisposed to ivermectin toxicity. The vet administers a test to determine an individual dog’s drug sensitivity, and for those who cannot take ivermectin, other alternatives exist. An alternative monthly tablet contains milbemycin as the heartworm preventative ingredient, offering additional protection against fleas, roundworms, hookworms and whipworms.

Monthly Topicals Hit the Spot

For those who prefer a monthly topical application, there are a couple of options available. One contains selamectin as the heartworm preventative ingredient, and the product also offers dogs protection against fleas, ticks, ear mites and sarcoptic mange mites. Another product contains moxidectin to provide protection against heartworms, and your dog will also be protected against fleas, roundworms, hookworms and whipworms. If your dog has been treated in the past for whipworms, which are very difficult to eliminate from the outdoor environment, this would encourage the use of the moxidectin product. If your dog spends his weekends camping, hunting or hiking with you in heavily wooded areas, your veterinarian may opt to protect your buddy from ticks by using the product that contains selamectin.

Prevention By Injection

An injectable form of moxidectin provides slow-release protection for up to six months against heartworms and hookworms. Geographical locations that see particularly high incidences of heartworms dictate more frequent injections for the most effective prevention. This option is best for those who live in such areas and prefer consistent protection without the fear of missing a dose. If your veterinarian determines this is the best option, he will recommend how often he must administer the drug to maintain maximum efficacy. If he instead recommends a monthly oral or topical product, use the reminder stickers in the packaging to place on your calendar each month. Or, use a reminder application on your mobile device so you never miss a dose toward keeping your canine companion safe from heartworm disease.