Lice are pesky parasites that most people associate with cases of head lice in schoolchildren, but they can also affect pets. Dogs, like humans, can be infested by lice, though it’s relatively rare compared to other parasites like fleas and ticks.

Loving pet parents need to be aware of the symptoms of a lice infestation in their beloved pooch and when they should seek treatment from their veterinarian. Let’s examine dog lice in more detail, including the symptoms, diagnosis, treatment, and prevention. We’ll start with the basics.

What Is the Difference Between Internal and External Parasites?

Internal and external parasites in dogs differ primarily in where they reside and the type of harm they cause. Here are some important differences.

Internal Parasites

Internal parasites live inside the dog’s body, typically within the gastrointestinal tract, lungs, or bloodstream.

Common internal parasites include:

• roundworms
• hookworms
• whipworms
• tapeworms
• heartworms

These parasites often cause symptoms such as vomiting, diarrhea, weight loss, lethargy, or a bloated abdomen.

Some, like heartworms, can cause severe damage to the heart and lungs, potentially leading to life-threatening conditions if left untreated.

Internal parasites are usually transmitted through ingestion of contaminated soil, water, or prey, as well as through mosquito bites in the case of heartworms.

External Parasites

In contrast, external parasites live on the surface of the dog’s body, often within the fur or on the skin. Examples include:

• fleas
• ticks
• lice
• mites

These parasites typically cause skin irritation, itchiness, redness, and, in some cases, secondary infections.

Fleas and ticks can also transmit diseases, such as Lyme disease and anaplasmosis, while mites can lead to mange. External parasites are usually contracted through contact with other infested animals or contaminated environments.

A Few More Differences

While external parasites can often be seen with the naked eye, internal parasites typically require diagnostic testing by a veterinarian for detection.

The treatment and prevention of internal and external parasites differ significantly. Internal parasites often require oral or injectable medications. External parasites are managed with topical treatments, sprays, or preventatives.

Regular vet check-ups and year-round parasite prevention are essential to protect your dog from both types of parasites and the discomfort or health risks they may cause.

What Are Lice?

Lice are tiny, wingless insects that live on the skin and hair of their hosts. Unlike fleas, lice are species-specific, meaning the type of lice that infests dogs cannot be transmitted to humans and vice versa.

There are, however, a few different species of lice that can infest your furry friend.

Dogs are susceptible to infestation by three species of lice: Linognathus setosus, a bloodsucking species, and two biting lice, Trichodectes canis and Heterodoxus spiniger.

These parasites differ in their feeding behaviors. Biting or chewing lice primarily feed on skin debris, although Heterodoxus spiniger, technically a chewing louse, also consumes blood, which is more common in sucking lice.

Dogs in poor health or living in unsanitary conditions are at a higher risk of heavy infestations. While Heterodoxus spiniger is rarely found in North America, Trichodectes canis is more common and poses an additional concern as it can act as an intermediate host for intestinal tapeworms, potentially transmitting them to infected dogs.

These types of lice are visible to the naked eye and measure about 2-4 millimeters in length. They spend their entire lifecycle on the host and are spread through direct contact or contaminated objects like grooming tools or bedding.

How Do Lice Differ From Other External Parasites?

Lice differ from other external parasites, such as fleas and ticks, in several significant ways. Unlike fleas, which can jump long distances, lice are wingless and cannot jump or fly.

They rely on crawling to move from one host to another, making direct contact between animals the primary method of transmission. This limited mobility also means lice infestations typically spread more slowly compared to the rapid spread of fleas.

Another distinction is in their feeding behavior. There are two main types of lice that infest dogs: biting lice, which feed on skin debris, and sucking lice, which feed on the host’s blood.

In contrast, fleas are exclusively blood-feeders, and ticks not only feed on blood but can also transmit serious diseases like Lyme disease.

Lice, while irritating, are less likely to pose a systemic health threat compared to these other parasites, although they can still cause secondary issues like skin infections or anemia in severe cases.

Lice spend their entire life cycle on the host, laying eggs (nits) that attach to the fur or hair shaft. Fleas and ticks, however, often lay their eggs in the environment, making infestation control more challenging as you must treat both your dog and his surroundings.

It’s easy to confuse lice with fleas, ticks, or mites because they all cause itching and discomfort. However, lice are slower-moving and tend to stay in one area, while fleas jump and mites burrow into the skin. Understanding these differences can help guide effective treatment and prevent misdiagnosis.

How Do Dogs Get Lice?

Dogs can get lice through direct contact with an infected animal. When dogs come in close contact with each other, such as during play, grooming, or living in close quarters, lice can transfer from one dog’s hair to another. This is particularly common in environments where many dogs are housed together, such as boarding kennels, shelters, or dog parks.

Another way dogs can acquire lice is through contact with contaminated objects. Lice and their eggs, known as nits, can cling to a dog’s bedding, brushes, collars, leashes, or toys used by an infested dog. If another dog uses or plays with these items, the lice can transfer and establish themselves in the new host’s coat.

While lice don’t survive long off a host, they can still pose a risk for transmission in environments where infested items aren’t promptly cleaned.

Poor health, a weakened immune system, or unsanitary living conditions can increase a dog’s susceptibility to lice. Dogs with matted fur or neglected grooming routines are particularly vulnerable because lice find it easier to hide and thrive in such conditions.

What are the Symptoms of Lice in Dogs?

While lice infestations are less common than fleas, they can still cause discomfort and health issues for your dog. Here are some common symptoms you might see:

1. Intense Itching: Dogs with lice often scratch, bite, or lick at infested areas, especially around the neck, shoulders, and ears.
2. Hair Loss: Prolonged scratching may lead to bald patches or thinning fur.
3. Visible Nits or Adult Lice: You might spot small, yellowish, or white nits (lice eggs) attached to your dog’s hair shaft. Adult lice may also be visible moving along the fur.
4. Dry, Flaky Skin: Skin irritation and dandruff are common, especially with chewing lice.
5. Scabs or Wounds: Open sores from constant scratching can become infected.
6. Restlessness: Dogs with lice may appear anxious or have trouble settling down due to the constant discomfort.
7. Anemia: In severe cases of sucking lice infestations, dogs may develop anemia, leading to lethargy and pale gums.

How Is Dog Lice Diagnosed?

If you suspect your dog has lice, a visit to the veterinarian is essential for confirmation and treatment. Lice infestations are diagnosed by beginning with a thorough physical examination, whereby your vet will inspect your dog’s coat for lice, eggs, or any signs of irritation.

Next, your vet will confirm the diagnosis with a microscopic analysis. This involves collecting a sample of your dog’s fur and examining it under a microscope. This will enable them to determine if the problems is lice or another type of parasite, like fleas or mites.

Finally, your vet will arrive at a differential diagnosis by ruling out other skin conditions that can cause similar symptoms, such as mange, flea allergies, or fungal infections. They will use physical and microscopic findings to do this.

How Is Lice in Dogs Treated?

The good news is that canine lice infestations are treatable. Treatment typically involves a combination of topical medications, environmental cleaning, and supportive care:

Topical Insecticides

Your veterinarian will likely prescribe products containing pyrethrin, permethrin, or fipronil as effective treatments against lice. These are available as shampoos, sprays, or spot-on treatments. It’s crucial to follow the product’s instructions carefully to avoid adverse reactions.

Oral Medications

In some cases, oral antiparasitic drugs like ivermectin may be prescribed, especially for severe infestations. However, ivermectin is not safe for certain breeds, like Collies, without prior testing for sensitivity.

Regular Grooming

Bathing your dog with a medicated shampoo helps remove adult lice and nits. Frequent combing with a fine-toothed flea comb can further aid in manual removal. This will also help with any other types of treatment your veterinarian has recommended.

Environmental Cleaning

Because lice can be spread by contaminated objects, you should wash all bedding, toys, and grooming tools in hot water to kill lice and eggs. Additionally, you should vacuum your home thoroughly to remove any loose hair or debris that may harbor nits.

Secondary Infections

If scratching has led to skin infections, your vet may prescribe antibiotics or medicated ointments to promote healing. It will be important to keep up with these treatments to prevent any more problems.

Can You Prevent Lice in Dogs?

You’ve probably heard the old saying, “An ounce of prevention is worth a pound of cure.” That’s why it’s important to do what you can to protect your dog from lice infestations in the first place. There are several things you can do to avoid this pesky problem.

First, you’ll want to regularly groom and bathe your pooch. In doing so, you’ll be able to spot signs of lice or other types of parasites early on before it becomes a bigger problem.

Since lice are spread by close contact with other infested dogs or their contaminated items, like collars and bedding, it’s a good idea to avoid sharing these things with other pet parents or pets. This can help reduce the likelihood of your dog getting lice and other contagious conditions.

It’s also important to get routine checkups with your veterinarian and discuss routine parasite prevention with them. They can recommend the best products for preventing fleas, ticks, and lice.

Furthermore, if you’re aware of other animals that are infested with lice, you’ll want to avoid letting your dog interact with them. Even if you don’t know for sure but notice other animals that are experiencing signs of itchiness or poor coat condition, you should think twice about letting your best friend interact with them.

Of course, sometimes you can’t avoid contact with other animals. But you can inspect your dog closely after he’s visited kennels, groomers, or dog parks. It’s in these kinds of communal environments that your dog is at greater risk of lice exposure.

Can You Get Lice from Your Dog?

It’s worth reiterating that canine lice are species-specific and cannot infest humans. This means you won’t contract lice from your dog, nor will your dog catch human lice. However, good hygiene and prompt treatment are essential to prevent the lice from spreading to other dogs in your household or community.

Since lice can also be transmitted via contaminated objects, keeping your dog’s toys, leashes, collars, and bedding clean is helpful in preventing the spread of lice to other household pets or visiting pet friends.

Final Thoughts

Though not as common as other parasites, lice can cause significant discomfort for your dog if left untreated. By knowing the symptoms, seeking timely treatment, and adopting preventive measures, you can protect your furry friend from this pesky pest. Regular vet visits, a healthy diet, and parasite control products are key to keeping your dog happy and healthy.

This content is for informational use only and does not replace professional nutrition and/or medical advice, diagnosis, or treatment. It is not a substitute for and should not be relied upon for specific nutrition and/or medical recommendations. Please talk with your veterinarian about any questions or concerns.