Heartworm Disease Prevention FAQs

Posted In: Canine Health & Wellness, Heartworm Disease

Heartworm disease is fatal and is unfortunately very common in our region. When it comes to preventatives, there are several options. Which one is right for your pet? Why do you need a prescription? Do you really need to give preventatives if your pet stays indoors? We answered the most frequently asked questions about heartworm disease and prevention:

What exactly is heartworm disease? 
Heartworm disease is one of the major health problems of dogs in the United States. Cats can contract it as well. Infected larvae from the mosquito enter the dog or cat’s blood stream just after the mosquito feeds. The larvae migrate through the tissues. Worms develop in the pulmonary artery and continue to grow in both size and numbers.

Heartworm disease can cause a weak pulse, pulmonary hypertension, congestive heart failure, and sudden collapse. It can also cause inflammation, blood clots, and can lead to liver or kidney failure. 

The Southeastern United States and the Mississippi River Valley have the greatest number of infected pets. This is because heartworm disease is transmitted by an infected mosquito. These areas can have unpredictable weather, and mosquitos have been known to surface, even in the winter months. 

At AMCMA, we follow the guidelines for testing, prevention, and treatment set forth by the American Heartworm Society.

With so many different options available for heartworm preventatives, how can you know which is right for your pet?
Talk to your veterinarian about the best heartworm prevention for your pet. He or she will take your pet’s age, size, medical history, and lifestyle into consideration before recommending a particular brand. At AMCMA, we find that many dog owners like the option of ProHeart® an injection that is given every six or twelve months. This is perfect for those who have a hard time remembering to give the preventative every month. Other popular options include Interceptor® Plus, a monthly chew that prevents heartworm disease and controls roundworm, hookworm, and tapeworm infections, and generic Milbeguard®. The price is an excellent value, and like other brands, you are eligible for a manufacturer rebate. 

How are prescription preventatives different from over-the-counter medications?
All heartworm preventatives are considered prescription products by the Food and Drug Administration (FDA), and require a prescription from your pet’s veterinarian. The FDA regulates products which are classified as a drug to treat specific problems. In order for your pet’s veterinarian to authorize your pet to take a prescription medication, your veterinarian must have a “Valid Veterinary-Client-Patient Relationship.” The FDA and State Veterinary Practice Boards guidelines say that a Valid Veterinary-Client-Patient Relationship exists when the veterinarian can be reasonably sure as to the health of the patient and the understanding of the client to the complexities of the problem being treated. For most routine preventative use, this means that the pet needs to be seen by the veterinarian dispensing or prescribing the medication within the last 12 months. 

When should I start my pet on heartworm prevention? 
Heartworm prevention should start when dogs are eight weeks old. If your dog is over six months old and hasn’t been on preventative consistently, you will want to be sure the dog has a current heartworm test before starting preventative. This is necessary because you want to make sure your dog does not have heartworms before starting the preventative. 

Do I need to have my pets tested for heartworms each year?
Most veterinarians will want to test your dog for heartworm disease each year. Because of the life cycle of the heartworm and limitations of which life stages the tests can detect, your pet should be retested six months after starting a preventative program, then annually after the six-month check. 

Do all of the pets in my household need to be on heartworm preventatives?
Yes. Companion animals are always at risk for parasites, even in colder months. In the past, heartworms were only seen as a true threat to dogs, but even indoor-only cats can die from complications due to heartworms if they bitten by a mosquito carrying the parasite.

If my pet stays indoors, does he need heartworm preventative? 
All dogs and cats are at risk of heartworm disease, even if the time they spend outside is limited. One mosquito bite is all it takes. 

One last bit of information: Prevention is key. It is less expensive and much safer to prevent heartworm disease than to treat it! 

The Animal Medical Center of Mid-America has veterinarians at three locations that can answer questions about your pet’s health. Call 314-951-1534 or click here to request an appointment online.