Heartworm Medication: Injectable vs Oral

Heartworm Disease and Your Dog

Odds are you've heard of heartworm disease, especially if you live with a dog. If heartworms find their way into your dog's bloodstream, and ultimately his heart, they can take up residency there, as well as in the pulmonary artery and other large arteries for up to five years. During this time, female heartworms, measuring 6 to 10 inches in length can produce millions of eggs from which baby heartworms will hatch and move on to the smaller blood vessels. If reading this is making you squeamish, think of how this fatal disease would make your pet feel. Fortunately, he will never have to, since you can bring him to Dr. Kristy Kreutzer, our veterinarian at Sunshine Animal Hospital in Superior, CO, for heartworm medication.


Beware the Mosquito

The good news is that your dog cannot catch heartworm disease from another dog at the dog park or boarding kennel. The bad news is he can get it from the bite of any infected mosquito and one blood-hungry mosquito can bite hundreds of dogs in its lifetime. If any one of these dogs happens to have heartworm eggs in its bloodstream, the biting mosquito can spread them to your pet as well. When heartworms are present in a dog, they can not only do damage to the heart, and ultimately cause heart failure, but if left alive, can go on to damage the lungs, liver, and kidneys. This is all the more reason pet guardians like you, as well as those all over, CO, including Broomfield and Louisville should make sure your dog is up to date on his preventative heartworm medication.

There is a choice when it comes to heartworm preventatives for your pets: injectable or oral. No matter which you choose, you need to have your dog tested to make sure he is not already infected. If he is, he needs treatment to kill the heartworms in his system before starting on a preventative. Preventative heartworm medication is not only good for your dog, it's necessary.

Injectable Heartworm Medication

Owners who opt for injectable heartworm medication need to bring their dogs in to the veterinarian for a shot either every six months, or once a year, depending on the type their veterinarian prescribes. Either way, there's no danger of forgetting to give a pet a monthly pill. This also ensures that the dog has semi-annual or annual checkups. In addition, many injectables also protect dogs from hookworms.

After your dog's first injection, keep an eye on him in case he has any adverse reactions. It doesn't happen often, nor with every type of injectable heartworm medication, but some dogs experience lethargy, weakness, vomiting, diarrhea, and seizures as side effects. More commonly, injection site reactions have been observed.

Oral Heartworm Medication

If you choose the option of protecting your dog with an oral heartworm preventative, you will be giving him a monthly chewable pill that, if he is like most dogs, he will think it's a treat. This is convenient in that you do not have to schedule an exam with the vet every six months. Although your dog will need a yearly exam in either case to renew his prescription. Should you choose to buy the medication in three- or six-month packaging, you can pick more up at the veterinarian's office without bringing him along. In addition to heartworms, some oral preventatives also provide protection from hookworms, roundworms, and tapeworms.

Ironically, the tastiness of oral heartworm medication can also work against it, as should a dog get into an unsecured package, he may gobble them up. The resulting overdose can cause vomiting, tremors, shock, and lack of coordination. If you have a puppy, his dosage will change as he gets bigger. Puppy owners need to monitor their dogs' weights so the vet can increase his dosage to make sure it remains appropriate for his size.

The Bottom Line

It's up to you to decide which form of heartworm preventative works best for you and your dog. The important thing is that he gets some form of prevention and that you keep him current with it. If you live in Broomfield, Louisville, Superior, or any of the surrounding, CO, communities, you can bring your dog to our practice, Sunshine Animal Hospital so that our veterinarian Dr. Kristy Kreutzer can examine him, test him for existing heartworm disease, and if he's clear, give you her recommendations and answer all your questions.


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