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Health & Wellness

Heartworm symptoms in dogs

It’s important to get your dog preventative medications.

What exactly are heartworms? How do dogs contract them? And most importantly, how can you get rid of them if you suspect your pup might be infected? If you’re seeking out advice for what to do if your best friend might have suddenly contracted this disease, look no further. We spoke with Dr. Zee Mahmood, DMV, a veterinarian at ZippiVet in Austin, Texas, to get the low-down on these parasites.

How do dogs get heartworms?

Heartworms, unlike the name suggests, are not a type of worm at all, but instead a parasite. According to Dr. Mahmood, “Heartworms, also known as Dirofilaria immitis, are a type of parasite that infects dogs, cats and ferrets, as well as many other wild animals. These parasites thrive in the blood and live in the heart, lungs and associated blood vessels.” One of the most common types of parasites contracted by dogs and cats alike — the heartworm larvae are transmitted through mosquito bites. Once in the bloodstream of an infected animal, the larvae can grow into adult heartworms — and can grow up to a foot long.

Heartworm prevention and medicine for dogs

The reality is that heartworm can be fatal if no treatment is performed, or if the disease has spread enough to irreversibly affect the function of the heart or lungs — but there’s good news. Preventable treatment plans are available and incredibly low maintenance. “Heartworm disease is almost 100% preventable in dogs by regularly giving them preventative medications. These medications, available through your veterinarian, are commonly given monthly, however some newer medications can be given once every 6 months or even once a year.” Dr. Mahmood said.

RELATED: What do you do if you find worms in your dog's poop

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Symptoms of heartworms in dogs

Some common warning signs that your dog might have heartworms include coughing, difficulty breathing, weakness or lethargy and loss of appetite. If you’ve begun to notice a change from your dog’s normal behavior, it’s always a safe bet to schedule a checkup with your local veterinarian, to test your dog’s blood and check for heartworms or assess them for other diseases.

Heartworm treatment for dogs

Once your dog has tested positive for heartworms, your vet will want to begin treatment.

“The most successful and recommended treatment protocol involves an injectable medication, melarsomine. This is given to treat and kill adult heartworms in a series of three injections, typically along with an oral antibiotic and an oral steroid.” Dr. Mahmood said. 

While there have been no proven side effects to heartworm medications, pet parents will still have to keep their pets on a tight lease while they’re undergoing treatment, in both a literal and figurative sense. “During treatment, it is recommended that dogs are confined to a kennel or crate and always kept on a leash for short bathroom breaks.” Dr. Mahmood said. “The most important thing for a dog to avoid while undergoing heartworm treatment is exercise. Any exercise can potentially cause a clot of degenerating worms to travel to a vital location in the body, causing serious and harmful complications.”

The most important thing to remember is to always play it safe when it comes to your best friend’s health. If your pup is displaying heartworm symptoms, it’s time for a check-up. Trust us, you and your pet will be thankful you did.

The Dig, Fetch Pet Insurance's expert-backed editorial, answers all of the questions you forget to ask your vet or are too embarrassed to ask at the dog park. We help make sure you and your best friend have more good days, but we’re there on bad days, too.

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