Tri-Heart Plus for Dogs Up to 25 lbs (1 Chew Tab) | On Sale | EntirelyPets Rx
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Tri-Heart Plus for Dogs Up to 25 lbs (1 Chew Tab) Video

Tri-Heart Plus for Dogs Up to 25 lbs (1 Chew Tab)

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  • Description
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Tri-Heart Plus for dogs is a heartworm preventative that also controls roundworms and hookworms. Tri-Heart Plus is a generic equivalent to Heartgard Plus, and requires a prescription from your veterinarian. It has the same active ingredients and is the same strength. Tri-Heart Plus is considered to be the #1 generic heartworm preventative recommended by veterinarians.

Key Benefits

  • Tasty flavored chewable tablets
  • Easy to administer
  • Small, easy-to-chew tablet for smaller or finicky dogs
  • Given once a month


Tri-Heart Plus chewable tablets are indicated for use in prevention of canine heartworm caused by Dirofilaria immitis and for the treatment and control of ascarids (Toxocara canis, Toxascaris leonina) and hookworms (Ancylostoma caninum, Uncinaria stenocephala, Ancylostoma braziliense) in dogs and in puppies six weeks of age.

How It Works

Tri-Heart Plus is used in the prevention of heartworm infection and the control and treatment of various other worm infections. Tri-Heart Plus contains two active ingredients: ivermectin, which interferes with the parasite's nerve transmission, causing paralysis and death of the immature heartworms (larvae), and Pyrantel pamoate, which also interferes with the parasite's nerve transmission, causes paralysis and death of intestinal worms.

Tri-Heart Plus is a registered trademark of Intervet Inc., d/b/a Merck Animal Health, a subsidiary of Merck & Co. Inc.


Active Ingredient Tri-Heart Plus Blue Tri-Heart Plus Green Tri-Heart Plus Brown
Ivermectin 68 mcg 57 mg 136 mcg
Pyrantel 114 mg 272 mcg 227 mg


View Tri-Heart Plus Drug Facts Sheet.

Tri-Heart Plus ivermectin/pyrantel chewable tablets should be administered orally at monthly intervals at the recommended minimum dose level of 6 mcg of ivermectin per kilogram (2.72 mcg/lb) and 5 mg of pyrantel (as pamoate salt) per kg (2.27 mg/lb) of body weight. The recommended dosing schedule for prevention of canine heartworm disease and for the treatment and control of ascarids and hookworms is as follows:

Dog Weight Chewable Tablets per Month Ivermectin Content Pyrantel Content Color Coding on Blister Card and Carton
Up to 25 lbs 1 68 mcg 7 mg Blue
26 to 50 lbs 1 136 mcg 114 mg Green
51 to 100 lbs 1 272 mcg 227 mg Brown
Over 100 lbs Give combination of chewables based on weight

Tri-Heart Plus ivermectin/pyrantel cewable tablets are recommended for dogs 6 weeks of age and older. For dogs over 100 lbs. use the appropriate combination of these tablets.


Remove only one chewable tablet at a time from the blister card. Because most dogs find Tri-Heart Plus chewable tablets palatable, the product can be offered to the dog by hand. Alternatively, it may be added intact to a small amount of dry food or placed in the back of the dog's mouth for forced swallowing.

Care should be taken that the dog consumes the complete dose, and treated animals should be observed for a few minutes after administration to ensure that part of the dose is not lost or rejected. If it is suspected that any of the dose has been lost, redosing is recommended.

Tri-Heart Plus chewable tablets should be given at monthly intervals during the period of the year when mosquitoes (vectors), potentially carrying infective heartworm larvae, are active. The initial dose must be given within a month (30 days) after the dog's first exposure to mosquitoes.

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

If the interval between doses exceed a month (30 days), the efficacy of ivermectin can be reduced. Therefore, for optimal performance, the chewable tablet must be given once a month on or about the same day of the month. If treatment is delayed, whether by a few days or many immediate treatment with Tri-Heart Plus chewable tablets and resumption of the recommended dosing regimen minimizes the opportunity for the development of adult heartworms.

Monthly treatment with Tri-Heart Plus Chewable tablets also provides effective treatment and control of ascarids (T. canis, T. leonina) and hookworms (A. caninum, U. stenocephala, A. braziliense). Clients should be advised of measures to be taken to prevent reinfection with intestinal parasites.


Tri-Heart Plus chewable tablets given orally sung the recommended dose and regimen, are effective against the tissue larval stage of D. immitis for a month (30 days) after infection and, as a result, prevent the development of the adult state. Tri-Heart Plus chewable tablets are also effective against canine ascarids (T. canis, T. leonina) and hookworms (A. caninum, U. stenocephala, A. braciliense).


In acceptability trials, Tri-Heart Plus chewable tablets were shown to be a palatable oral dosage form that was consumed at first offering by the majority of dogs.


All dogs should be tested for existing heartworm infection before starting treatment with Tri-Heart Plus chewable tablets which are 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 chewable tablets.

While some microfilariae may be killed by the ivermectin in Tri-Heart Plus chewable tablets at the recommended dose level, Tri-Heart Plus chewable tablets are 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.

Keep this and all drugs out of the reach of children. In case of ingestion by humans, clients should be advice concerning cases of ingestion by humans.


Store at controlled room temperature of 59-86° (15-30° C). Protect product from light.

Adverse Reactions:

In clinical field trials with ivermectin/pyrantel, vomiting or diarrhea within 24 hours of dosing was rarely observed (1.1% of administered doses). The following adverse reactions have been reported following the use of ivermectin at the recommended dose: depression/lethargy, vomiting, anorexia, diarrhea, mydriasis, ataxia, staggering, convulsions and hypersalivation.


Studies with ivermectin indicate that certain dogs of the Collie breed are more sensitive to the effects of ivermectin administered at elevated dose levels (more than 16 times the target use level of 6 mcg/kg) than dogs of other breeds. At elevated doses, sensitive dogs showed adverse reactions which included mydriasis, depression, ataxia, tremors, drooling, paresis, recumbency, excitability, stupor, coma and death. Ivermectin demonstrated no signs of toxicity at 10 times the recommended dose (60 mcg/kg) in sensitive Collies. Results of these trials and bioequivalency studies support the safety of ivermectin products in dogs, including Collies, when used as recommended.

Ivermectin/pyrantel has shown a wide margin of safety at the recommended dose level in dogs, including pregnant or breeding bitches, stud dogs and puppies aged 6 or more weeks. In clinical trials, many commonly used flea collars, dips, shampoos, anthelmintics, antibiotics, vaccines and steroid preparations have been administered with ivermectin/pyrantel in a heartworm disease preventive program.

In one trial, where some pups had parvovirus, there was a marginal reduction in efficacy against intestinal nematodes, possibly due to a change in intestinal transit time.


Tri-Heart® Plus flavored chewable tablets are an FDA-licensed product, indicating they are safe and effective when used as recommended on the label. All dogs should be tested for existing heartworm infection before starting treatment with Tri-Heart® Plus.
In clinical trials, many commonly used flea collars, dips, shampoos, anthelmintics (deworming medications), antibiotics, vaccines and steroid preparations have been administered with ivermectin/pyrantel in a heartworm disease prevention program. For questions about specific medications, please consult your veterinarian.
Ivermectin/pyrantel, the active ingredients in Tri-Heart® Plus, have a wide margin of safety at the recommended dose level in dogs, including pregnant females, breeding males and females, and puppies 6 weeks or older, according to the package insert.
No. Tri-Heart® Plus is labeled for use in dogs to prevent heartworm disease and not for the treatment of heartworm infections. The package insert contains this precautionary statement: "Infected dogs must be treated to remove adult heartworms and microfilariae before initiating a program with Tri-Heart® Plus flavored chewable tablets."
No. Tri-Heart® Plus is not approved for use in cats.
Tri-Heart® Plus flavored chewable tablets can be obtained only by prescription and are available from your veterinarian.
The American Heartworm Society (AHS) is an excellent source of information for both pet owners and veterinarians. Please visit for further details.


Review Summary
63 Reviews
79% (50)
17% (11)
3% (2)
0% (0)
0% (0)
98% Recommend this product (62 of 63 responses)
By Lisa
Willow Grove, PA
Fantastic Experience!
October 26, 2020
I have used several online pharmacies for my pets and, without a doubt, these folks are the best! Since we have several dogs and a cat, buying from the vet is definitely not feasible. I'm so happy I found Entirely Pets Pharmacy! They send a request to my vet and within a day or two (no supposed Covid delays like some places) they contacted me that my order was being processed and then shipped- easy as that! Not only are their prices the best I've found, but their customer support is excellent.

Merchant Response:Lisa, this review warms our hearts and is motivation for us to continue on! We have some big improvements coming in the near future to help get more orders out more quickly and an even better customer expereicne. Thanks for being a great customer. Thanks for sharing pictures of your fur babies, they are cute!
Low Cost Easy Ordering Fast shipping Haven't found any yet and about to place my 3rd order!
By Gene I.
Roseville MN
Review for Tri-Heart Plus for Dogs Purchase
April 9, 2015
Your price was the lowest that I found on- line and the product was delivered in a prompt manner. Very satisfied with your on-line pharmacy! I would use your site again for ordering product for my dog. Thanks!
Great price prompt delivery of product got exactly what I ordered simple ordering process none
By Margarita
Miami, fl
Very good product
June 14, 2023
Very good product and price
By Deborah
North Carolina
Quality Product at Excellent Price
May 17, 2023
We've typically ordered products for our dog from one supplier; however, because of rising prices, I decided to compare prices across the internet before placing the last order. EntirelyPets Pharmacy, without a doubt, has the absolute best prices. Website is easy to navigate and shipping was quick.
By DoxieMom
March 8, 2023
Happy to find a product to fit our needs for a good price! With small dog going with us on a cross country road trip to the South East, we needed protection against heart worm for a month only. It was perfect to be able to purchase in smaller quantity! Also, customer service was great, shipping prompt!
Thank you!
Much less expensive than many other brands!
By Candice
Houston, TX
Give all my docs this product!
February 17, 2023
Great product. Great service. Very timely delivery.
By Helen
October 2, 2022
very nice and pleasant
By Carol
Very Happy
May 1, 2022
I have been very happy with this product in the past, with my 1st rescue dog. I have a new rescue so I ordered her some Tri-Heart. It was a good price and arrived in a short time.
Big pill can be broken into pieces
March 17, 2022
I like that the pill can be broken into smaller pieces so my dog won’t try to swallow a big pill and choke on it. And my dog takes it like a treat. I also like that the back of the box has a calendar to keep track monthly.
Pill can be broken into pieces Calendar on the box to keep track monthly
By Yvonne
Great product
February 26, 2022
Price is good and my dogs are protected
By Stephie
Plant City, FL
Tri-Heart Plus for Dogs
February 18, 2022
Good Product, Good Price. Wish it came with softer tablet, but if did it would probably be more expensive like Heart Gard.
By Stephanie
DC Area
Simple and seems good
September 14, 2021
My dog eats these with only a slight hesitation, so this is good. I do wish they were soft chews, he seems to like those better. But since he was diagnosed with cancer, my vet and I decided that less poison is better for him, thus choosing this two poison pill over those with three or four.
Less poisons Dog eats them with only some fuss Still poison Not a soft chew
By Moonraven
Great product
June 16, 2021
Easy ording.
By Cathy
Best ingredients at the best price
June 4, 2021
Tri-Heart contains the best ingredients for coverage of Heartworm and other parasites at the best price.
By Martha
Florence, Alabama
Tri-Heart Plus for dogs
May 26, 2021
This was my first purchase of Tri-Heart Plus for dogs. I had been using Heart Guard for my dogs for many years. Heart Guard was getting very expensive for 4 dogs. Nothing is too good for my four legged babies. Of course, if you can get something as good for less money, why not? After checking out Tri-Heart, and with vet approval, I decided to give it a whirl. Guess what? Tri-Heart has the same great benefits as Heart Guard. I would definitely recommend Tri-Heart to all dog owners, like myself.
Less expensive, works well for prevention of heart worms.
By Virginia W.
Medford, Oregon
ordering Tri-Heart-Pluus for our dog.
May 15, 2021
Very pleased with order, not only was the price fantastic, the order was received in record time. Awesome service.
By Linda
Triheart plus
May 15, 2021
Great service and fast shipping.
The price was a little less than what I would have paid at the vet’s office.
By Yankey
Really good
April 19, 2021
My dog does really well on this product
By Brian R.
Marshallton, DE
Hard to navigate web site
March 23, 2021
Couldn’t get order processed through web site on numerous occasions, never got email customer service said I would get
Merchant Response:Brian, we are taking steps to improve our site navigation. Thank you for your feedback. At this time, our notification emails are nearly all online and working again. System upgrades have had some bugs. Your next order will be better-taken care of.
By Julie L.
Great product
March 6, 2021
Very nice people but they were updating their system & we were told it was coming on a weds.... they hadnt even sent it yet. one week later it shows up- they waited 1 week bbefore sending it to us .. so the communication is bad with entirely pets
Merchant Response:Hi Julie, Very true. We were having some growing pains. All new pharmacy and shipping software lead to some delays. The team here worked overtime to work through the bugs. Hope to have you back for your next order. Take care.
great products --- comparable prices we have ordered 2 times from them... took more than 2 weeks because it wasnt sent for over a week each time...very slow in filling orders...
By Ange
Entirely Pleased
February 28, 2021
This is my first order with this company and my first trial of Tri-Heart Plus. I usually use Heartgard but my vet doesn't carry it anymore so he wanted me to try Interceptor. My chihuahua has had reactions to several medications so I'm cautious as to what I give her. After giving her the Interceptor for 2 months, each time she would be listless for a few days, just not her usual self.
So I found this med. I checked the ingredients (the same ingredients and same amount) as the Heartgard, it had good reviews and a great price. I consulted with my vet. He agreed to authorize the prescription for Tri-Heart Plus and I am "entirely pleased."
I will be reordering.
Same medication as the Heartgard Great savings on the price My dog wouldn't chew the pill. I had to break it in pieces and add to peanut butter. I would really prefer a chewable treat option, but at this price I'm not going to complain.
By john P.
great transaction by entirely pets
January 24, 2021
excellent transaction from start to finish
By Mari
December 23, 2020
This med did not come in a package altogether, rather in packs and parts of packs with different dates. One was labeled, Use First.
I don 't like this and in the future, want an entire pack with same dates on all tabs.
Med itself seems OK.
By Joyce
Porter, Tx
Tri-Heart Plus for dogs
November 15, 2020
Great value. Very fast delivery, I ordered on Friday and received product on Monday.
By Diana
Lexington, KY
Good Product
November 11, 2020
I treat all my dogs with Tri-Heart Plus and every vet visit confirms, it works :)
By Ellen
Great finding this online pet supply
October 29, 2020
perfect for our dog and great delivery
By Eric
Central Fl
Works, our Yorkie eats it without problem
October 19, 2020
I'm a bit of a pragmatist... first, the product has to work, and while this product doesn't do flea's, it DOES do much more than the standard heartworm / flea combo chew at a much better price.

So, after years of buying the other, I switched to this and a separate flea treatment. Could be happier. Second biggie is will she eat it and does it have any adverse effects? Our Yorkie eats it without fuss, no side effects, and she is well protected.

Very happy with Tri-Heart and highly recommend.
Broad spectrum protection Dog likes taste Price Doesn't have Flea/tick protection (but not really a con, when you work out the price)
By Dog l.
Chapel Hill, North Carolina
Excellent product
October 14, 2020
I have been using this product for years and have been very pleased with the protection it has given my dogs. The price was good and having it delivered is a plus.
By Kelly
DE Forest, Wi
Best price
August 20, 2020
The price is excellent!
Merchant Response:Hi Kelly, We are always finding ways to increase our shipping speed. Thanks for being a great customer.
I think shipping could be a little faster
By Dog l.
Washoe Valley Nevada
Does the trick
August 19, 2020
I purchase Tri-heart plus for my dogs and it works well. Fast shipping and reasonable price.

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