Pharmacy Spotlight: Heartgard® Plus Chewables
Drs. Foster & Smith Educational Staff


  • Medication type: Prescription-only, heartworm and intestinal wormer

  • Active ingredient: Ivermectin & pyrantel pamoate

  • Dosage form: Chewable treat

  • Manufacturer: Merial

  • Major use: For the prevention of heartworm infections as well as elimination of certain roundworms and hookworms.

  • How it works: Ivermectin interferes with the nerve transmission within the immature heartworms (larvae), causing their paralysis and death. Pyrantel pamoate interferes with the nerve transmission within intestinal worms, causing their paralysis and death. Death of the worm occurs when it is discharged from the animal. The worm cannot survive outside the host's body. Ivermectin/pyrantel pamoate heartwormers are also available in generic or bio-equivalent forms, such as Tri-Heart® Plus.

Mixed Hound PeteHeartgard® Plus Chewables

Dog's Name: Pete
Breed: Mixed Hound
Age: 6 years

His story: Pete's owners had not thought seriously about giving Pete heartworm prevention all year long until their next-door neighbor's dog acquired heartworm disease. They were very close to their neighbors and saw first hand the pain and expense they went through to get their dog well. It became abundantly clear to Pete's owners how serious the situation was and that a dog could die from the disease - and even from the treatment for the disease. Pete's owners talked to their veterinarian and learned that there were other heartworm cases in their area.

Outcome: Pete is on Heartgard® Plus all year long now, and his owners now have peace of mind. The bonus is that the owners don't have to worry about intestinal worms, either. He still gets a heartworm test every year from his veterinarian.

For full details on this medication, download the free patient information sheet.