Heartgard Plus for Dogs is a medication intended to prevent the development and transmission of the parasite that causes heartworm disease. Heartworm disease is transmitted by the bite of infected mosquitoes and is endemic in many parts of the US. Heartworm disease can be debilitating and even fatal.
How to use Heartgard Plus
Heartgard Plus is a beef-flavored chewable medication that is administered once a month. A prescription from a veterinarian is necessary, and before starting a program of heartworm prevention, the dog should be tested and confirmed to be free of heartworms because Heartgard Plus will not kill adult heartworms. Dogs infected with partially mature heartworms may exhibit vomiting and diarrhea if they are given Heartgard Plus.
It is essential to protect dogs from heartworm disease. While there is a treatment for established cases of heartworm disease, the treatment is expensive and time-consuming, and can cause life-threatening reactions in the dog being treated.
How it works
Heartguard Plus contains ivermectin and pyrantel, two anti-parasitic agents. When an infected mosquito bites a dog, the immature Dirofilaria immitis worms enter the dog's bloodstream. Inside a dog, it takes around seven months for the worms to mature. After maturity, the worms start to produce offspring, and, gradually, over time, large numbers of worms accumulate in the dog's heart, lungs, and blood vessels.
When given once a month, Heartguard Plus kills any immature worms that have gained access to the dog's body during the previous month. In addition to controlling heartworms, Heartgard Plus will also kill any hookworms and roundworms within the dog's digestive tract.
Adverse events are rarely seen in response to Heartguard Plus. It can be safely used with puppies as young as six weeks and during pregnancy and lactation.
It should be noted that dogs carrying MDR mutations, which are common in collie breeds and whippets, can be very sensitive to ivermectin, and caution should be used when first administering Heartgard Plus to these dogs. However, clinical studies have shown that the level of ivermectin in Heartgard Plus is generally well-tolerated by dogs with MDR mutations.
Where is heartworm found?
Most cases occur in warmer, southern states, especially along the coastlines, but cases have been reported from all 50 states, and it seems to be spreading. Currently, many dogs are transported from shelters in the south to shelters in the north, and some of these dogs are infected with heartworm, which can then become established in the local mosquito population and transmitted to other dogs.
Does Heartgard Plus need to be given year-round?
Most veterinarians recommend giving Heartgard Plus 12 months a year, especially in warmer climates.