What is heartworm in cats?

The heartworm in cats is the same heartworm that lives in dogs. A mosquito bite transmits it from a dog to a cat, a cat to a cat, or even from a wild animal to a cat. It's a parasitic worm that lives in the heart and lungs.

Dr. Heather Kovacevich
The Drake Center

How do cats get heartworm?

From a mosquito bite. A mosquito would come and bite your cat, and as they're having a blood meal, they put a little bit of larva on the skin, which then gets into the bloodstream and turns into a spaghetti-like worm that lives in their heart and lungs. So it's mosquito-transmitted.

What do veterinarians recommend as heartworm prevention for cats?

There are lots of products for cats. There are oral and topical versions. One that we carry here is called Bravecto, but there are many options on the market. They're either given once a month or every other month for heartworm prevention.

How do you spot heartworm symptoms in cats?

The natural hosts for heartworms are dogs. Cats don't get it as frequently as dogs, but they can get it even though they're an unnatural host. Sometimes the worms don't develop all the way to become mature worms. They stay in the larval stages, and the body clears them out.

But other times, they do become adult worms. If that is the case, those cats typically develop respiratory symptoms like coughing, labored breathing, pale gums, and lethargy like not being able to exercise. They can also have GI upset like vomiting, poor appetite, and weight loss.

So whenever you bring your cat in for these symptoms, we'll keep that in the back of our minds and potentially test for it.

How will a veterinarian diagnose heartworm in your cat?

With a very simple blood test. We need a few drops of blood that we'll send to the laboratory. We'll get the test results back within a few days.

Why is early detection and diagnosis of heartworm so important?

Heartworms in cats are different than in dogs. There are no treatments for cats. There is no injection that we can give them to treat heartworms. The worm would just have to die on its own, which is why it's so important to diagnose it early. This way, we could help the body to prepare for the worms and treat any side effects that the worms cause. We would also want to be able to prevent them in the future. Of course, an early treatment's always better, but just to reiterate, there is no treatment for feline heartworm disease that will kill the worms.

If you still have other questions and you'd like to reach out to us, you can call us directly at (760) 456-9556, you can email us, or you can reach out on social media. But please do reach out, and we'll get back to you as fast as we can.

Cat heartworm - FAQs

Dr. Heather Kovacevich
The Drake Center

How is heartworm prevented in cats?

There are oral as well as topical heartworm preventatives. It depends on what works for you and your family or the cat. Some cats don't want to take a pill, and the topical option would be easier, but there are both options.

When should I start heartworm prevention for my cat?

This is a great question because it depends on where you live in the country. Heartworm isn't as common a disease in California. It's much more common in the Midwest, along the Mississippi River, the Gulf Coast, and the East Coast. So it depends on where you live as well as the lifestyle of the cat. If the cat lives outdoors, they should be on prevention year-round, especially if you live in those areas. I would start it when they are kittens as young as eight weeks.

How effective is heartworm prevention for cats?

It's completely preventable if you are diligent about giving it at the recommended time. If you give an oral preventative once a month and you never falter from that, your cat will not get heartworm disease.

Does my cat still need a heartworm test if they are on prevention?

No, we typically don't test cats. Especially as a kitten, we just start the prevention. The only reason that I would recommend a test is if they're having symptoms. If they're having breathing problems or GI upset, then we might want to test for heartworm. But it's not something that we would routinely test every year, at least not in our area in California.

Can prevention be used to clear a heartworm infection?

No, it differs. Prevention entails preventing the disease. It's not going to treat the cat if they already have heartworms. Like I said before, there is no treatment for heartworm in cats. There are treatments for the side effects that they cause, but there's no treatment to kill the actual worm.

Is there any holistic or over-the-counter cat heartworm prevention?

No, nothing works. If you could put your cat in a bubble so they would never get bit by a mosquito, that would be great, but obviously, that's not plausible.

Can I do anything in my cat's environment to reduce the risk of heartworm?

Keeping your cat indoors will greatly reduce the risk because you're going to have fewer mosquitoes in your indoor environment. That doesn't mean a mosquito can't come into your house now and then. I kill them from time to time in my own house. But keeping them indoors does lower the risk of heart disease and cats.

What should I do if I miss a dose of my cat's heartworm prevention?

You should just go ahead and give the next dose. Alert your veterinarian that you missed a dose. If you live in an area with high incidence of heartworm disease, they might recommend a test. But you should just keep giving the dose. In fact, even if a cat has heartworm disease, we still keep them on the preventative because we're preventing more worms from developing. It's not wrong to give the next dose, but talk to your vet about it.

If you still have other questions and you'd like to reach out to us, you can call us directly at (760) 456-9556, you can email us, or you can reach out on social media. But please do reach out, and we'll get back to you as fast as we can.