Lice in Dogs and Cats: A 2025 Guide to Detection, Treatment, and Prevention 🐶🐱🪳

Hello, I’m Dr Duncan Houston BVSc. Lice are less common than fleas or ticks in pets, but when infestations occur, they can cause intense itching, blood loss, and discomfort. This guide breaks down how to spot, treat, and prevent lice in dogs and cats—and how to keep your home lice-free in 2025. 🧼

🦠 What Are Lice?

🪳 Lice are six-legged, wingless, flat insects
👁️ Visible to the naked eye—unlike mites or fleas
🗓️ Entire life cycle is 21 days, lived entirely on the host

Types of Pet Lice:

Dogs: Trichodectes canis (chewing) and Linognathus setosus (sucking)
Cats: Felicola subrostrata (chewing)

Lice are host-specific. Dog lice don’t infest cats or humans. Cat lice won’t survive on dogs or people. 👥

📉 Symptoms of Lice in Pets

🤕 Severe itching, restlessness
🧴 Scruffy, dry coat
📉 Patchy hair loss
👂 Most common around ears, neck, shoulders, and anus
🩸 In puppies: anemia or shock in severe cases

Note: In puppies, a heavy infestation may cause up to 25% blood loss over several months. ⚠️

🧬 Transmission

Pets get lice through:

👃 Direct contact with an infested animal
🪥 Contaminated brushes, bedding, or grooming tools

Lice are slow movers and don’t jump like fleas, so infestations often spread in crowded or poorly cleaned environments (shelters, kennels, grooming areas). 🧼

🔍 Diagnosis

Lice are visible with the naked eye. Look for:

🪳 Adult lice crawling on fur
🕸️ White, oval-shaped nits (eggs) stuck to hair shafts

Your veterinarian can confirm diagnosis by examining the fur under a microscope. 🩺

💊 Treatment Options

Lice are generally easy to eliminate. Your veterinarian may recommend:

🧴 Insecticidal shampoos
🔄 Repeated treatments every 2 weeks (total of 3–4 rounds)
💊 Isoxazolines (e.g. fluralaner, sarolaner, lotilaner, afoxolaner)—often only 1–2 treatments needed
💉 Fipronil or selamectin (topical spot-ons)

If the coat is matted, your vet may recommend shaving. 💇

🧼 Environmental Cleanup

🧽 Wash or dispose of all pet bedding
🧴 Disinfect grooming tools between pets
🌬️ Vacuum carpets and furniture
🧤 Sanitize kennels and high-turnover spaces regularly

Foggers: Not usually necessary unless infestation is severe. 🫧

🛡️ Prevention Tips

🛁 Bathe and groom pets regularly
🐾 Avoid direct contact with stray or infested animals
🧴 Use monthly parasite control products (especially in shared pet spaces)
🧼 Clean brushes, collars, and beds between pets

📱 Ask A Vet: Help With Lice Control

💊 Choosing the right anti-lice treatment
📋 Setting a treatment schedule
🧽 Cleaning advice for homes and shelters
🐾 Identifying lice vs. fleas or dandruff

Talk with a vet anytime at AskAVet.com or via the app. 🐶📲

✅ Summary: Lice in Dogs & Cats

🪳 Lice are visible parasites that stick to your pet’s hair and suck blood or chew skin
🐾 Cause itching, hair loss, and possible anemia in severe cases
🧴 Treat with insecticide shampoos or monthly parasiticides
🧽 Clean bedding and grooming tools to prevent reinfection
👥 Lice are species-specific and do not live on humans

Lice are treatable and preventable. With fast treatment and proper hygiene, your pet will be comfortable again in no time. 🐕🧼🐈

— Dr Duncan Houston BVSc