Heartworm Information

Our Greenfield Vet Team Can Prevent & Treat Heartworms in Dogs & Cats

Seeing your animal suffer from a disease or illness is hard enough—knowing that disease or illness could have been prevented makes it even more difficult. Our Greenfield vet staff, also serving Oak Creek and surrounding Wisconsin communities, urgently asks all local pet owners to make sure their pets are adequately protected against heartworms.

dog and cat sleeping on each otherWhat Are Heartworms?

Heartworms are actual worms that can grow up to about a foot in length. They grow inside blood vessels supplying blood to the major organs of an animal's body, including the heart and lungs.

They are carried in their larval stage by mosquitoes and transmitted into mammals (cats, dogs, coyotes, foxes, rarely humans) via mosquito bites. Once inside the animal host, a heartworm can grow, mature, and eventually mate and produce offspring. Heartworms can live for up to 7 years in dogs and up to 3 years in cats.

How Heartworms Affect Cats, Dogs & Other Animals

If left untreated, heartworms can cause serious and potentially fatal consequences, since they begin to block blood flow to vital organs. In the earliest stages there may be no signs, but as the heartworms grow signs become progressively worse:

  • Persistent mild cough
  • Aversion to exercise
  • Quick to fatigue
  • Weight loss
  • Decreased appetite and occasional vomiting
  • Distended abdomen due to fluid retention caused by heart failure 
  • Difficulty walking 
  • Seizures
  • Caval syndrome (sudden breathing difficulty, pale gums, dark urine, and/or collapse)

Heartworms affect cats differently than dogs. Feline symptoms are generally more subtle or come on more abruptly—including sudden death. 

Even after heartworms have been treated and removed, long-standing chronic problems can remain. Fortunately, prevention is simple: just a once monthly pill with a prescribed dose based on your pet's breed and size. 

Heartworm Treatment & Prevention with Our Greenfield Veterinarian Team

We recommend the American Heartworm Society's "think 12": get your pet tested for heartworms every 12 months and administer heartworm preventive medication to your pet every month—for life.  If your pet is diagnosed with heartworms, our Greenfield vet team can help by providing necessary heartworm treatment. Interventions address the underlying infestation as well as secondary complications, and may include:

  • Surgical removal of heartworm blockage
  • Medications to kill the heartworms 
  • Medications to control adverse effects, including antibiotics and steroids
  • Exercise and activity restriction 
  • Close follow-up with our vet team 

Are You On Top of Your Pet Parasite Prevention Regime? Schedule Your Appointment Now with a Veterinarian in Greenfield 

To meet with a veterinarian in Greenfield WI and get your cat or dog up-to-date with its parasite prevention, contact the Greenfield Veterinary Clinic at (414) 282-5230.


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