What to do if your dog has fleas

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What to do if your dog has fleas - Vetster

Fleas are the most common external parasite on dogs and other furry friends but can be difficult and time-consuming to treat. Quickly treating infestations and preventing future infestations is important for pet owners to keep dogs happy and healthy. Read on to learn:

  • How are fleas diagnosed and treated in dogs?
  • What are the common symptoms of fleas in dogs?
  • How do dogs get fleas?
  • How can I prevent fleas on my dog?
  • Why is flea prevention important?

Fleas can spread disease to dogs and dog owners, infest the home, and cause unpleasant flea allergy dermatitis (FAD) symptoms. Choosing a flea treatment and prevention product that is safe and effective with the help of a veterinarian is important for the safety of your dog and wider household as well.

How does a veterinarian diagnose and treat flea infestations in dogs?


A diagnosis of flea infestation can be made with the observation of adult fleas or the presence of flea dirt (little black spots that smear red or brown on damp paper towel) on dogs. A diagnosis may be suggested if a dog is experiencing flea allergy dermatitis symptoms, such as itchiness or hot spots, even if no adult fleas or flea dirt can be found. Most dogs show few to no symptoms of fleas unless they are allergic to flea saliva. If a dog is experiencing flea allergy symptoms or associated conditions caused by fleas, they are treated alongside the fleas themselves.

The best way to effectively treat fleas is the prolonged use of vet-approved flea prevention for at least three months to address the entire flea life cycle. Flea prevention is available in different formats, including chewable tablets, medicated collars, and topical flea treatments. Most flea treatments only kill adult fleas, sometimes also killing flea larvae. Eggs and pupae are much hardier and most preventives are not sufficient to exterminate these stages of the life cycle. As such, prolonged treatment is essential. As fleas mature into larvae and adults, they become susceptible to the effects of preventive medications. If preventive treatment is stopped prematurely, the surviving eggs that develop into adults will continue to breed and thrive.

How do I treat fleas in my home?

Some vet-approved flea products remain active when shed in the pet’s dander, so they also treat the environment. If additional home treatment is needed, thoroughly wash and vacuum all carpet, bedding, and soft dog toys. After vacuuming, immediately throw the bag away or empty the canister outdoors to prevent the fleas from escaping back into the home. Consider using an environmental spray that includes an insect growth regulator or consulting with an exterminator. Always consult a veterinarian to ensure any pest control products are safe to use around pets.

Can I treat fleas naturally?

Natural products and homeopathic flea treatments do not work and can be dangerous to use on or around dogs. There is no scientific evidence to show they are effective. Combing and grooming may give an appearance of naturally eliminating fleas, but they remove only a tiny, insignificant number of adult fleas from your dog. You can consult a qualified veterinarian online to discuss the best flea prevention options for your dog.

a dog laying in the grass while a person shows a flea on their finger in the foreground

What are the common signs of fleas in dogs?


Fleas are small insects that live on a pet’s skin and in the fur, ingesting blood meals and breeding rapidly on the body. Fleas are the most common external parasite in dogs and infested dogs may show few to no symptoms unless the dog is allergic to flea saliva. Dogs are commonly allergic to flea saliva which leads to symptoms of flea allergy dermatitis. Common symptoms of an allergic reaction to fleas include:

Fleas are also a potential source of exposure to tapeworms, which can be seen passing in the stool or under a dog’s tail. Anemia can also occur in small puppies or dogs with heavy flea infestations as the fleas ingest blood meals. Symptoms of anemia include weakness, lethargy, loss of appetite, rapid breathing, and pale gums. Note: it is extremely rare for large and otherwise healthy adult dogs to develop anemia from flea bites.

How did my dog get fleas?

To understand how dogs contract fleas, it’s important to understand the flea life cycle and how they spread. Adult fleas eat and mate on a mammalian host, then lay their eggs in animal fur. These eggs are not sticky and fall off the host animal into the environment. Hosts can be other pets or wild animals. Flea eggs can be found anywhere an infested host has been, but are found in the highest concentrations where an animal rests and spends the most time. Eggs hatch into larvae which survive on fallen flea dirt, flea droppings, and pet dander. Larvae have an easier time surviving with some protection from harsh sun, regular cleaning, and heavy traffic.

Next, the larvae spin a cocoon and enter the pupal stage. Flea pupae are extremely well protected and cannot be killed by flea prevention or treatment products. The pupae can hatch quickly, after only a few days, but are also able to survive extended periods of time in this stage, emerging as adult fleas when a host is available. Adult fleas then hop on to a new host or reinfect the original host and reenter the life cycle.

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“Dogs are exposed to adult fleas anytime they pass through or lay down in an area where an infested animal has been,” explains Dr. Jo Myers, a veterinarian at Vetster. “This includes common areas in apartment complexes, outdoors in shady areas, and near screened-in windows and porches. Your dog doesn’t have to spend a lot of time outside to end up with fleas.”

Can fleas be prevented on dogs?


Oral medications, topical treatments, and flea collars are available for dogs as vet-approved flea prevention. They work by quickly killing fleas that have bitten the dog, preventing them from breeding, or repelling fleas. Some formulations remain active in pet dander that’s shed into the environment and kill larvae there. It is important for pet parents to choose the correct preventive for their pet’s overall health and lifestyle, as some over-the-counter products can be dangerous or ineffective. Some topical flea treatments are not safe for use on dogs that live around cats. Consult a veterinarian to learn what products are safe and effective. In addition, always use size and species-appropriate prevention as directed to avoid toxicity, overdoses, and ineffective doses. The continued use of monthly flea prevention for all pets in the household  is necessary to prevent infestations.

What can I do if my dog has fleas?


If you find fleas or flea dirt on your dog, or if your dog is experiencing symptoms of flea allergy dermatitis, consult a veterinarian for the best treatment. Treatment is necessary for all the pets in the home, even if no fleas or allergy symptoms are present. Treating the home may not be necessary, but it can hasten the elimination of the flea population. Once the fleas are eliminated, keep your pets on flea prevention to prevent future flea infestations.

Can I catch fleas from my dog?


Yes. Fleas freely feed on and spread disease to any mammalian host. Many diseases, such as bartonella and plague, are dangerous for people as well as pets. Flea bites in humans can also become itchy and inflamed, causing discomfort and irritation. Homes become infested when any pet is infested with fleas as they mature and hide in the carpet, furniture, and bedding. Flea prevention in dogs is important for pet parents to prevent the spread of disease. If you have questions about fleas or finding the best flea preventative for your dog, you can consult an online vet through Vetster from the comfort of your home.

FAQ - What to do if your dog has fleas


What type of flea products do veterinarians recommend?

Veterinarians recommend safe and effective flea control products for your dog and know which over-the-counter products are unsafe or ineffective. Natural or home remedies for fleas do not work and may be dangerous to use on or around dogs. Safe flea products can come in oral treatments, topical liquids, and flea collars.

How long does it take to get rid of fleas on a dog?

Every life stage needs to be addressed to effectively treat a flea infestation. Flea eggs and pupae are nearly impossible to kill, so flea treatment must be used for at least three months to kill them once they mature.

Will fleas in the house go away on their own?

Home treatment is not always necessary if all pets in the home are being treated with highly effective flea prevention. However, treating the home by washing and vacuuming all bedding, carpeting, furniture, and soft dog toys can help reduce the flea population while treatment of individual pets is ongoing.

What is the best flea treatment for dogs?

Talk to a veterinarian to learn which flea treatment is best for your unique situation. Some over-the-counter products are dangerous or ineffective, and natural or homeopathic flea treatments do not work. Many can be dangerous to use on or around pets, especially cats.