Procedures / Heartworm treatment

Heartworm treatment cost: what to expect in 2026

Heartworm treatment costs $1,000–$3,000 for dogs in 2026, staging and injections included. Cats have no approved cure; prevention is the whole game.

Fair range: $200 – $3,000 per full courseEstimates updated 07-2026Model estimate · vet review pendingHow we compute this
Estimate

What should it cost near you?

Transparent math: a typical general-practice price for your pet, adjusted for clinic type and your region. See exactly how this is computed →

Fair range $200 – $800 per full course

A quote inside this range is ordinary. Above it isn't automatically overcharging — but every dollar above should map to a line you can question (diagnostics, meds, hospitalization). Well below the range: ask what's included, since the cheapest way to a low number is leaving things out.

Typical price by pet

At a general-practice vet, U.S. national average. Emergency and specialty hospitals run higher — use the calculator's clinic-type selector, and pick your state there for local numbers.

PetGeneral-practice range
Cat$200 – $800
Small dog (under 25 lb)$1,000 – $1,800
Medium dog (25–60 lb)$1,200 – $2,300
Large dog (over 60 lb)$1,500 – $3,000

Cost by pet size, at a glance

General-practice range for each pet, on a shared scale — pet size is one of the biggest cost drivers for this procedure.

Cat$200–$800Small dog$1,000–$1,800Medium dog$1,200–$2,300Large dog$1,500–$3,000

The math, worked out

Every estimate here is the same formula — a typical general-practice price, scaled by clinic type and your region — so you can reproduce it for your own quote. For a medium dog (25–60 lb):

General-practice baseline: $1,200 – $2,300

At an emergency hospital (×1.75): $2,100 – $4,030

Then multiply by your region — roughly ×0.82 in a lower-cost state, ×1.36 in a higher-cost one. The calculator above does all of this for your exact state and clinic type.

What moves the price

  • Dog weight: melarsomine is dosed by the kilogram, so a 90 lb dog's injection series costs multiples of a 15 lb dog's
  • Disease stage: advanced cases need more stabilization, sometimes an echocardiogram, and carry more risk
  • Two-injection vs the three-injection American Heartworm Society protocol; most vets now use three
  • Cats are a different story entirely: no approved cure exists, so cat costs are supportive care rather than treatment

Lines you may see on the bill

Legitimate in the right circumstances — the "when" column is the test to apply. Paste your full bill into the decoder to check each line at once.

Line itemTypical costWhen it's legitimate
Doxycycline pre-treatment month$50 – $200Part of the American Heartworm Society protocol: a month of antibiotics weakens the worms before injections. Expect it on the bill.
Overnight observation after each injection$100 – $400Many practices keep dogs for monitoring after melarsomine shots. Reasonable given injection-day risks; ask whether it is bundled.
Sedatives for the rest period$20 – $80Two-plus months of strict crate rest is the hardest part, and many dogs need trazodone or similar to tolerate it. Cheap and often necessary.
Re-test at 6–9 months$40 – $100Confirms the treatment cleared the infection. Skippable only in the sense that you would not know whether it worked.

How much your region matters

Vet prices track local cost of living. This procedure on a medium dog (25–60 lb) runs roughly $1,440 in a lower-cost state like Mississippi versus about $2,380 in a higher-cost one like California — same care, different overhead. Use the calculator above for your own state.

When this comes up

  • A positive antigen test at an annual screen, often before any symptoms
  • A soft, persistent cough or tiring on walks
  • Weight loss and reluctance to exercise as the disease advances
  • In late disease: labored breathing or a fluid-filled belly, which is an emergency

Cost of waiting

The American Heartworm Society describes untreated heartworm disease in dogs as progressive and ultimately fatal, with damage to the heart and lungs accumulating while you wait. The Society also recommends against relying on 'slow-kill' preventive dosing as a substitute for treatment, since worms keep scarring the arteries for the years they take to die. Earlier is also cheaper: staging and treatment cost less when the disease has done less.

Can you avoid it?

Melarsomine is an injectable, veterinary-only arsenical; no home version of this treatment exists. The budget lever is prevention: $10–$30 a month protects a dog for less per decade than one treatment course, and for cats prevention is the only protection there is.

Common questions

How much does heartworm treatment cost for a dog?

Plan on $1,000–$3,000 for the full staged protocol at a general practice: staging bloodwork and chest x-rays, a doxycycline month, the melarsomine injection series, and rechecks. Small dogs sit near the bottom of that range and large dogs near the top, because the drug is dosed by weight.

Why can't my cat get heartworm treatment?

No drug is approved to clear adult heartworms in cats, and the dog drug is not safe for them. The American Heartworm Society's guidance for infected cats is supportive care and monitoring, which is what the $200–$800 cat range on this page reflects. That is also why the Society is emphatic that monthly prevention is the only real protection a cat has.

Is the cheaper 'slow-kill' method a real option?

Vets hear this question constantly because the price gap is real. The American Heartworm Society recommends against slow-kill (monthly preventives plus antibiotics, waiting years for the worms to die naturally) except when injections are truly not an option, because the worms keep damaging the lungs the whole time. If the quote is unaffordable, ask about spreading the staged protocol's costs over a few months instead.

How does prevention compare in cost?

About $10–$30 a month, or roughly $120–$360 a year, versus $1,000–$3,000 for one treatment course. A decade of prevention costs about what a single infection does, before counting the permanent lung damage treatment cannot undo. Few pet-care numbers are this lopsided.

Sources & further reading

Where our inputs come from and the authorities worth knowing. Base ranges are compiled from published vet-cost surveys, pet-insurance claim ranges, and clinic price listings.

How this page is built: a typical general-practice price range for this procedure by pet type, adjusted for clinic type (general / emergency / specialty) and your region's cost of living — compiled 07-2026 from published sources. We're building a reader-submitted bill dataset to refine these ranges; once enough exist they appear above. Full detail on the methodology page. This is an estimate, not a quote. Have a bill? Decode it →