Do Heartworms Physically Hurt a Dog?

Canine heartworms can develop when your dog is bitten by a mosquito carrying infective heartworm larvae. While the worms can take several months to mature, mate and reproduce, they eventually will populate your dog’s heart, lungs and even blood vessels. This invasion of your dog’s cardiopulmonary systems can create associated symptoms that range from uncomfortable to painful for your dog, and if left untreated, can result in death.

It can take as long as seven months for heartworm larvae to be detected in your dog’s bloodstream. According to the American Heartworm Society, heartworms typically start out residing in the lower caudal pulmonary arteries and begin to create inflammation, followed by migration to adjacent areas in the heart and the caudal vena cava, one of the body’s largest veins. This can impede blood flow and create symptoms of congestive heart failure, which includes labored breathing and respiratory distress. This can be uncomfortable or painful for your dog depending on the severity of the condition.

Left untreated, heartworm can begin to compromise your dog’s other internal organ systems. Your pup may experience kidney and liver problems or chronic infections. You may find your dog tires more easily when battling heartworm disease and may have trouble or pain with breathing, especially during periods of strenuous exercise. In severe cases, when heartworms impede blood flow to the brain, your dog runs the risk of losing consciousness. If he stumbles or falls, it could result in painful injuries.

According to the American Heartworm Association, early detection and treatment can often cure canine heartworm and halt the often painful progression of symptoms of the disorder. Blood and antigen tests or ultrasounds performed by a vet can detect the presence and severity of heartworm disease. Vets use a variety of different macrocyclic lactone anthelmintic medications to treat heartworm. Ask your vet about the most appropriate approach based on your dog’s age, weight and physical condition.

Preventative measures can protect your dog against the invasive heartworm. Monthly topical, oral or injectable medications can be recommended by a vet. Routine medical exams and checkups also can help a vet catch heartworm early and reduce the potential pain and damage your dog is subjected to. Pay close attention to your dog’s physical behavior and appearance. Early signs of heartworm may include cough, listlessness or swollen abdominal cavity due to fluid retention.