Heartworm Medicine for Dogs

Heartworm Medicine and Prevention for Dogs

Heartworm disease in dogs is fatal if left untreated. Pets get the illness when a mosquito bites them and infects them with larvae. Since these insects are everywhere, veterinarian's recommend having a year-round prevention plan. By doing this you can protect your dog from heart failure, lung disease, and organ damage. Learn how the parasite life cycle works and the heartworm medicine for dogs that is available.

Heartworm Life Cycle

Adult heartworms live in the heart of infected dogs. Here, they produce microfilariae that remain in the canine’s bloodstream. When a mosquito bites an infected dog, they take in microfilariae that grow into larger larvae over a period of two weeks. Larvae then travel to the mosquitoes mouth where they wait for the insect to feed so they can enter their new host. After the transfer, larvae spend the next 65 days maturing and migrating to the dog’s heart where they remain over a 5-7 year lifespan.

Symptoms and Heartworm Prevention for Dogs

Most canines don’t show signs of heartworm disease until it progresses. If you notice your pet has a decreased appetite, is losing weight, lacks energy, or has a cough, consult a veterinarian. They will diagnose your pet which is step one of deciding their treatment plan.

For canines who only have the infection, they receive heartworm medicine for dogs known as preventives. This type of medication kills the immature form of larvae but does not kill adult worms. This is why testing is key in determining which stage of heartworms your canine has. With your veterinarian’s guidance, you can select the proper heartworm prevention for dogs, schedule routine testing, and limit your pet’s exposure to mosquitoes.

Prescription Heartworm Medicine for Dogs

There are four heartworm medicines for dogs that Petco carries—Heartgard, Iverhart, Sentinel, and Tri-Heart. The active ingredient Ivermectin is used in Heartgard Plus, Iverhart Plus, and Tri-Heart Plus. Ivermectin kills the immature form of the heartworm while also helping control intestinal worms. Prescription medications and pills with this ingredient are safe to use on dogs 6 weeks or older.

Milbemycin Oxime is the other active ingredient used in Sentinel heartworm products. It works by killing the immature stage of the heartworm larvae and the adult stage of hookworms, roundworms, and whipworms. It differs from Ivermectin by also helping control fleas. Sentinel for dogs is safe to use on dogs 4 weeks or older, weighing 2 pounds or more.