Heartworm disease plagues hundreds of thousands of pets annually in the United States—especially in warm, moist regions like Florida where mosquitoes thrive. Characterized by tiny, microscopic worms that mature in an infected pet’s heart and lungs, heartworm disease is capable of causing serious disease—something all pet owners should be wary of. Fortunately, the condition is 100% preventable with diligent heartworm prevention products. Here are answers to some common heartworm-related questions.

Question: What is heartworm prevention and how does it work?

Answer: A wide variety of heartworm prevention products are available today, in the form of a chewable tablet, spot-on liquid, or long-lasting injection. All these products work in a similar fashion—to eliminate any larval heartworms in the body. Basically speaking, a heartworm preventive is a type of parasiticide that targets immature heartworms, preventing them from becoming adults. Many heartworm preventives will also address other worm-like parasites in the pet’s body. Note that most heartworm preventive products are formulated to address only immature worms, so once worms reach their next stage of development, these medications are ineffective. This is why timely administration of preventive products is crucial in avoiding disease development. 

Q: Why do I need a prescription for my pet’s heartworm prevention?

A: At this time, heartworm prevention is not available over the counter like many flea, tick, and other parasite preventive products. The Food and Drug Administration (FDA) requires that heartworm products be used only under a licensed veterinarian’s directive, to ensure their proper use. Since administering preventives without knowing a pet is heartworm-positive can lead to severe effects, any pet who has not been receiving a routine prevention protocol must be tested for heartworm disease prior to beginning a regimen. 

Q: Can my puppy or kitten start heartworm prevention? If so, when?

A: Immature heartworms take approximately six months to develop into adult worms, the only stage that will show up on a heartworm test. For this reason, testing puppies and kittens before starting heartworm prevention is not necessary, although the American Heartworm Society recommends beginning preventive medications as early as the product label allows, which will be around 8 weeks of age for most. Since the risk of a puppy or kitten developing heartworm disease is similar to that of adults, beginning a preventive routine as early as possible is ideal. 

Q: Does my pet really need heartworm prevention year-round?

A: No matter where you live in the United States, year-round heartworm prevention is a good idea. If you and your furry friends live in Florida, however, prevention is absolutely crucial. Our state is one of the hardest hit with heartworm infections, thanks to our warm, humid environment. Since mosquitoes spread heartworm disease, the infection is naturally a greater concern in regions where these pests thrive. That being said, if you live part of the year in a dry, desert climate, heartworm still pose a risk—in fact, heartworm disease has been diagnosed in all 50 states. For this reason, the American Animal Hospital Association (AAHA) and the AHS recommend that all pets receive year-round, broad-spectrum control against heartworms, intestinal parasites, and fleas. 

Q: Can my cat get heartworm disease?

A: Yes! While dogs are the natural heartworm disease host, meaning that worms can and often do mature to adulthood in the body without treatment, the disease manifests differently in cats. Our feline friends can still become infected with heartworms by an infected mosquito, but most of the larvae will not mature into adult heartworms. Since the large adult worm burdens typically seen in dogs are associated with higher morbidity and clinical signs, heartworm disease in cats often goes undiagnosed. However, immature heartworms can cause respiratory problems in cats, and year-round prevention is still recommended for this species. 

Q: My pet tested positive for heartworm disease—now what?

A: Don’t panic! Your Narcoossee Oaks veterinarian is well-equipped to treat your pet for heartworm disease. We follow the American Heartworm Society’s guidelines to offer your pet the best possible outcome. Depending on the severity of your pet’s condition, treatment typically begins with a series of oral medications, injections, and strict exercise restriction. We may also recommend laboratory tests and hospitalization while your pet is treated. Rarely, pets will require surgery to remove adult heartworms. 

At Narcoossee Oaks Animal Hospital, our veterinary team is dedicated to treating and preventing heartworm disease. If you need assistance in choosing a heartworm preventive or have additional questions about our treatment protocol, contact us.