Short answer: Heartworm disease in dogs is treated with a veterinarian-supervised protocol built around a series of melarsomine dihydrochloride injections that kill the adult worms, combined with strict rest and exercise restriction for several months while the worms die off. It works, but it is expensive, hard on your dog, and takes patience — which is exactly why year-round prevention matters so much.
I'm Preston Smith, co-founder of Bully Sticks Central. We're a dog-treat company, not a veterinary clinic, so treat everything below as a plain-English overview to help you talk with your vet — not as medical advice. Heartworm treatment should always be handled by a licensed veterinarian.
What is heartworm disease?
Heartworm disease is a serious, potentially fatal condition caused by parasitic worms (Dirofilaria immitis) that live in the arteries of the lungs and, in heavier infections, the heart. Dogs get it from the bite of an infected mosquito — there's no dog-to-dog spread. Over months to years the worms grow, multiply, and damage the lungs, heart, and other organs. According to the American Kennel Club, heartworm has been diagnosed in all 50 states.
What are the symptoms of heartworm in dogs?
Early infections often show no signs at all, which is why annual testing matters. As the disease progresses, watch for:
- A mild, persistent cough
- Reluctance to exercise or tiring quickly after activity
- Decreased appetite and weight loss
- A swollen belly from fluid buildup in advanced cases
If you notice any of these, see your vet promptly. Caught early, heartworm is far more manageable.
How is heartworm disease treated in dogs?
Treatment is a multi-step process that typically unfolds over several months:
- Confirm and stage the disease. Your vet runs blood tests and often X-rays to confirm the infection and gauge how advanced it is.
- Stabilize your dog. Dogs showing symptoms may need to be stabilized first, and vets often prescribe several weeks of a preventive plus an antibiotic (doxycycline) and a steroid to reduce the risk of complications before the worm-killing injections begin.
- Kill the adult worms. The core treatment is melarsomine dihydrochloride, given as a series of deep injections into the back muscles — usually one injection, then two more about a month later. Melarsomine is the only FDA-approved drug for killing adult heartworms.
- Enforce strict rest. This is the part owners underestimate. As the worms die they break apart and travel to the lungs, and a raised heart rate can cause dangerous blockages. Most dogs need weeks of severely restricted activity — no running, jumping, or hard play.
- Re-test. Roughly six months after treatment your vet re-tests to confirm the worms are gone.
The American Heartworm Society publishes the treatment guidelines most U.S. vets follow, and it's a solid resource if you want to go deeper.
How do you keep a dog calm during heartworm recovery?
Weeks of enforced rest is genuinely tough — a bored dog is a restless dog, and restlessness is exactly what you're trying to avoid. Long-lasting chews are one of the easiest ways to burn mental energy while your dog stays physically still. A good chew keeps them settled in one spot instead of pacing the house.
We're big believers in single-ingredient chews for exactly this reason: they're 100% natural, 100% real meat, fully digestible, and contain no rawhide. Our bully sticks are ethically sourced from grass-fed American and Argentinean farms and give most dogs a satisfying, quiet chewing session. If your vet has okayed light chewing during recovery, softer options like a beef trachea can also help pass the time. Always confirm with your vet what's appropriate for your dog's stage of recovery, and supervise chew time.
How is heartworm disease prevented?
Prevention is dramatically cheaper, safer, and easier than treatment:
- Give a monthly preventive year-round. Options include chewables, topicals, and a twice-yearly injection. The FDA recommends year-round prevention even in cooler climates.
- Test annually. Even on preventives, yearly testing catches any gaps early.
- Reduce mosquito exposure by eliminating standing water and keeping dogs in during peak mosquito hours when you can.
The bottom line
Heartworm disease is treatable, but it's a long, costly, and stressful road for both you and your dog. A monthly preventive — a few dollars and a few seconds a month — is by far the smarter play. Talk with your vet about the right prevention plan, keep up with annual testing, and if your dog is already in treatment, follow the rest protocol to the letter.
Every product we make is 100% high-quality guaranteed, because keeping your dog healthy and happy is the whole point. Stay vigilant, and keep those tails wagging.
This post was last updated at July 17, 2026 20:34
