What Does Heartgard Plus Protect Against? | EntirelyPets Rx
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What is Heartgard Plus and What Is It Used for?


Mosquitoes are a constant nuisance to pets and their owners, but they can also pose a serious threat as vectors that spread deadly parasites. In fact, mosquitoes play a vital role in the lifecycle of heartworms, as heartworms must pass through mosquitoes while in their larval stage before they can mature to adulthood in a host animal. Once the worm has passed through the insect and entered your pet’s bloodstream, the parasite can reproduce and cause lasting damage to vital organs.

If left untreated, a heartworm infestation will progress into what is known as heartworm disease. This term describes a group of symptoms that affects pets when large heartworms begin to cause significant damage to an animal’s vital organs. This damage can lead to severe lung disease, heart failure, and ultimately death. Heartgard Plus offers protection against heartworms and works to kill heartworms before they pose a serious threat to your pet’s health.

Heartworm Disease in Dogs


Heartworms are capable of living in a wide variety of host species as microscopic microfilaria in the blood stream. The microfilariae then linger in the blood stream until a feeding mosquito happens to consume the infected blood. Once in the mosquito, they require 10-14 days to develop into infective larvae before being transmitted to another animal when the mosquito feeds again. Once inside a host animal, the worms will take approximately 6 months to mature into adult worms.

Infected dogs will not initially exhibit symptoms; though if left untreated, they will likely experience a persistent cough, fatigue, inappetence, and weight loss. Should the infestation progress, they will also develop a swollen stomach due to an excess of fluids in their abdomen. Dogs at this stage may also experience heart failure, as the worms begin to create life-threatening blockages in the heart; these dogs are said to be suffering from caval syndrome.

Caval syndrome refers to the advanced stages of a heartworm infestation in which the parasites obstruct the vena cava, causing serious complications in your pet’s cardiovascular system. The syndrome is marked by a sudden onset of heavy breathing, pale gums, and dark or bloody urine. These symptoms indicate that a dog is in need of emergency surgery to remove the heartworms; without immediate surgery, it is highly unlikely that a dog suffering from caval syndrome will survive.




How Heartgard Plus Works


Heartgard Plus combines two medications to prevent infestation from three types of parasites that commonly affect dogs. The formulation includes ivermectin to prevent the growth and development of heartworms, ensuring that they never cause your dog danger or discomfort. Though ivermectin is also the active ingredient in Heargard, Heartgard Plus stands apart through its inclusion of Pyrantel Pamoate, which treats and prevents both roundworm and hookworm infestations.

Both worms can cause diarrhea, anemia, weight loss, and fatigue in infected dogs; due to the similarity of their symptoms, hookworm and roundworm infestations can mask the early signs of heartworm disease. Aside from this confusion, hookworms can themselves prove fatal in younger dogs. The worms enter puppies either through direct ingestion from the environment or through the skin. Once inside a dog, different species of hookworms will cause different symptoms with the most dangerous species causing potentially fatal levels of blood loss in puppies.

Roundworms are nearly always transmitted before birth and inhabit an animal’s intestines, where they swim freely. These worms are the most common parasitic worm found in dogs and can require several treatments to exterminate from your pet. Though these worms do not pose a threat to your dog’s life, they do pose a threat to you and your family. Roundworms can be spread from an infected dog to a human with children and pregnant women being the most susceptible to infection.

Heartgard Plus works to eliminate all three parasites and to prevent future infestations for a full month after each dose. The medication is also easy to administer, as each chewable tablet features a palatable beef flavor that dogs love. The monthly medication can also be given to your pet year-round to ensure that your pet stays safe from worms at all times; however, a prescription from your veterinarian is required to purchase and use Heartgard Plus.

Identifying Heartworm


The similarity of symptoms between infestations of heartworms, hookworms, and roundworms can make it difficult to tell which parasite is affecting your pet. Though Heartgard Plus treats all three types of infestations, there are other dewormers available that treat only hookworms or roundworms. Because Heartgard Plus requires a prescription, it may be easier to use these other treatments for dogs that only have hookworms or roundworms.

Many dewormers that are available over-the-counter eliminate both hookworms and roundworms. Because of the different protocols for different infestations, it’s important that you know the exact condition of an infested pet before attempting to provide treatment. Your veterinarian can determine if your pet needs heartworm medication or you can test for heartworms at home with an antigen test kit.

Side Effects


It’s also important to be aware of the risks associated with Heartgard Plus before administering the medication to your pet; for example, collies and other herding dogs are known to have adverse effects to high levels of ivermectin. Pets with known allergies to ivermectin or to pyrantel may also require a medication that uses different active ingredients to eliminate parasites.

Aside from these cases, side effects of Heartgard Plus are rare when administered correctly. In the rare case that a pet experiences adverse effects from the medication, they may exhibit dilated pupils, tremors, and loss of body weight. Side effects are exacerbated with improper usage and can potentially be fatal, so it’s also crucial that you follow your veterinarian’s direction exactly when using Heartgard Plus.


Using this medication appropriately also means administering the correct dosage to your pet. Each package comes in a formula that is ideal for dogs in a particular weight range. The chewable tablets should be administered once per month and must not be swallowed whole by your pet. If your pet does receive an overdose, indicated by vomiting, diarrhea, and incoordination- then it is vital that you seek emergency veterinary medical treatment immediately.

We hope that this article as fully explained the benefits and protections offered by Heartgard Plus, as well as the risks associated with it. For more information on related medications, check out the articles below!