Vet Reviewed

By The Farmer's Dog | June 2, 2023

If you suspect that your dog has fleas, there’s no need to flee in terror. While the parasites can be a threat to your dog’s health, they’re treatable. And if your dog doesn’t have fleas, there is a lot you can do to protect them from the pests.

Here are some tips about how to make, or keep, your best buddy flea free.

The basics about fleas

Fleas are tiny bloodsucking insects that can’t fly, but can leap quite a distance. There are thousands of types of fleas, but only a few of them infest dogs. These include one called Pulex simulans, another called the dog flea, and dogs’ most common flea tormentor: the cat flea. This may sound surprising—but, to be fair, the cat flea is also the one that most often attaches itself to cats.

While most fleas complete their life cycles in 3 to 8 weeks, some of them can spend almost a year waiting for an appropriate host to present itself. For that reason, and because their eggs and pupae are sturdy, they can be tough to vanquish.

Flea infestations in dogs are preventable and treatable, but it’s important that you don’t ignore them.

How to tell if your dog has fleas

If your dog has fleas, they may show that they’re feeling itchy by scratching, licking, rubbing, or chewing their skin. These can be signs of flea allergy dermatitis, which is brought on by the saliva in flea bites and is the most common skin ailment in American dogs

Fleas and their eggs are very small, but you may spot evidence of them on your dog. Fleas’ droppings can appear as dark specks on your dog, while their eggs may look like white specks. If you see dark flecks on your dog and want to check whether they’re flea droppings, put them on a damp white paper towel. If they’re flea droppings, they’ll turn brown and then red as they absorb moisture.

If your dog has contracted tapeworms by ingesting fleas, you may see tapeworm segments in your dog’s stool; those can look like grains of rice. You may also see the worms crawling around near your dog’s anus, or on their bed.

You may have trouble spotting fleas in your home, because they tend to seek dark, sheltered areas, like inside cracks in floors, underneath furniture, or deep in carpeting.

Are fleas dangerous to dogs?

Most dogs with fleas will be fine after treatment, but the parasites do pose some threats.

Dogs with flea allergy dermatitis may scratch and chew themselves so much that they lose fur, get skin irritations, scab up, and develop skin infections.

Dogs with fleas can also get anemia. Fleas drink considerable quantities of blood for their size—a female can consume 15 times her body weight—and that’s bad for dogs with severe infestations.

If dogs eat fleas—which they often do when infested—they can contract tapeworms. These can be especially dangerous to puppies. Fortunately, tapeworms aren’t as likely to cause serious illness in otherwise healthy adult dogs, but they still require treatment.

While dogs can technically be infected with plague from flea bites, in practice this almost never happens.

Can humans catch fleas from dogs?

If your dog has fleas, they might bite you. The good news is that cat and dog fleas won’t live on people—we’re not suitable hosts for them—and it’s likely the worst consequence you’ll experience is getting itchy. Still, they can sometimes transmit disease to humans, so you should try your best to keep them away from you.

How to get rid of fleas

If your dog has fleas, you’ll have to treat both them and their environment. Banishing a flea infestation altogether is often a challenge, and can take months. If you live with other animals that can host fleas—more dogs or cats, for example—they will need to be treated as well.

Talk to your veterinary healthcare team about which treatments might be right for your dog. There are a variety of options available, including topical products, oral medication, and injections, and your choice will depend on your vet’s advice, your dog’s needs, and your personal preferences. Whatever you use, follow the instructions on the label and your vet’s advice closely.

Wash all of your dog’s clothing, bedding, and soft toys, using hot water if it’s safe to do so. Thoroughly vacuum any areas where they spend time. Throw the vacuum bag away outside of your house.

Depending on the severity of the infestation, you may want to use insecticides that kill fleas—due to the length of fleas’ life cycle, you may need to do so more than once. Consult with a vet about what’s safe for your dog, and with your own doctor about what’s right for your family.

If your dog spends ample time outside, you may need to clean and treat their favorite outdoor hangouts on your property as well. Some humans use organisms called nematodes, which eat flea larvae, for this purpose.

How to prevent your dog from getting fleas

Many humans give their dogs oral medication, topical liquids, or flea collars to prevent flea infestations. Some flea-preventative medications also protect against ticks. These all have pros and cons—including variable levels of efficacy and potential side effects. Work with your veterinary healthcare team to determine the right choice for your dog and the best program to help keep fleas and other parasites at bay.

Remember: If you notice an unexplained change in your dog’s behavior, or anything else that could be a sign of fleas or another health issue, call the vet’s office so that they can look into it.