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Tri-Heart Plus for Dogs

by Merck

This item requires prescription approval.

Prescription medications are currently limited to CA residents. More states coming soon!!

Original price $21.99 - Original price $37.99
Original price
$21.99 - $37.99
Current price $21.99
Size: Up to 25 lbs
Count: 6 Month

Tri-Heart Plus is for use in dogs to prevent canine heartworm disease by eliminating the tissue stage of heartworm larvae for a month after infection and for the treatment and control of ascarids and hookworms.

  • Beef Flavored for a highly palatable treat
  • Cost-effective and easy-to-administer chewable tablet
  • Tri-Heart Plus chewable tablets are available in three dosage strengths for dogs of different weights
  • Tri-Heart Plus chewable tablets contain a proven combination of ingredients to protect your dog and ensure your complete peace of mind.

Consult with your veterinarian for proper dosage and course of treatment.


Use on dogs only.


All dogs should be tested for existing heartworm infection before starting treatment with Tri-Heart® Plus which is not effective against adult D. immitis. Infected dogs must be treated to remove adult heartworms and microfilariae before initiating a program with Tri-Heart® Plus.

While some microfilariae may be killed by the ivermectin in Tri-Heart® Plus at the recommended dose level, Tri-Heart® Plus is not effective for microfilariae clearance. A mild hypersensitivity-type reaction, presumably due to dead or dying microfilariae and particularly involving a transient diarrhea has been observed in clinical trials with ivermectin alone after treatment of some dogs that have circulating microfilariae.

Food and Drug Interactions

Be sure to tell your veterinarian what medications and supplements you give your pet.

When replacing another heartworm preventive product in a heartworm disease preventive program, the first dose of Tri-Heart® Plus must be given within a month (30 days) of the last dose of the former medication.

Human Warnings

Keep this and all medications out of the reach of children.

Possible Side Effects

The following adverse reactions have been reported following the use of the ingredient ivermectin at the recommended dose: lethargy, vomiting, loss of appetite, diarrhea, eye dilation, loss of coordination, convulsions and hypersalivation.

If your pet experiences any of these adverse reactions, contact your veterinarian

Contact your veterinarian if you believe your pet is experiencing side effects.

Product Administration


Product Form

Chewable Tablet


Ivermectin and Pyrantel


Store at controlled room temperature of 59-86° F



Prescribing Info/Brochures