Lyme Disease in Dogs: Symptoms, Causes, Diagnosis, Treatment & Prevention

Lyme disease in dogs is a bacterial infection caused by Borrelia burgdorferi and transmitted primarily through the bite of infected ticks. Dogs can become infected after spending time in areas where ticks are present, particularly wooded, grassy, or brushy environments.

Many dogs that are exposed to the bacteria do not develop obvious symptoms. However, some dogs can develop fever, tiredness, loss of appetite, swollen joints, and shifting lameness. In more serious cases, Lyme disease can affect the kidneys and, less commonly, the nervous system or heart.

Important: If you suspect your dog has Lyme disease, contact a veterinarian. Symptoms can overlap with other tick-borne infections and joint conditions, so diagnosis should be made by a veterinary professional.

What Causes Lyme Disease in Dogs?

Lyme disease is caused by the bacterium Borrelia burgdorferi. It is transmitted by infected ticks, particularly black-legged or deer ticks (Ixodes species).

A tick generally needs to remain attached for a period of time before transmitting the bacteria. Promptly finding and removing ticks can therefore reduce the risk of transmission.

Dogs are often more exposed to ticks than people because they may walk through tall grass, bushes, forests, and other tick habitats.

Lyme Disease Symptoms in Dogs

Not every infected dog becomes visibly ill. When clinical signs occur, common symptoms include:

• Fever
• Loss of appetite
• Low energy or lethargy
• Painful or swollen joints
• Lameness
• Lameness that shifts from one leg to another
• Reluctance to move
• Swollen lymph nodes

Intermittent, shifting lameness is one of the characteristic presentations of Lyme disease in dogs.

Some dogs may develop more serious complications. Kidney involvement is particularly concerning and can become life-threatening. Neurological complications and heart involvement are reported less frequently.

Do Dogs Get a Lyme Disease Rash?

A common misconception is that dogs with Lyme disease will always develop the classic “bull’s-eye” rash associated with human Lyme disease.

Dogs generally do not develop the characteristic expanding erythema migrans rash that is commonly discussed in people. Therefore, the absence of a visible rash does not rule out Lyme disease in a dog.

Veterinarians generally look at the dog’s clinical signs, tick exposure, geographic risk, and laboratory results rather than relying on a skin rash alone.

How Is Lyme Disease Spread to Dogs?

The infection is transmitted when an infected tick bites a dog.

The general cycle is:

Infected tick → tick attaches to dog → bacteria are transmitted → dog becomes infected

Dogs do not normally transmit Lyme disease directly to people through ordinary contact. However, a dog can carry unattached ticks into the home, where those ticks could subsequently bite a person or another animal.

How Is Lyme Disease Diagnosed in Dogs?

Diagnosis can be challenging because some dogs can test positive for antibodies without developing clinical illness.

A veterinarian may consider:

• The dog’s symptoms
• History of tick exposure
• Geographic location and travel history
• Physical examination
• Blood tests
• Lyme antibody testing
• Other laboratory tests
• Tests for other possible causes of the symptoms

Antibody testing can support a diagnosis, but a positive result does not automatically mean that Lyme disease is responsible for a dog’s current symptoms. Veterinarians interpret test results together with the clinical picture.

Routine bloodwork may also be performed to evaluate the dog’s overall health and look for complications, particularly when kidney disease is suspected.

Lyme Disease Treatment for Dogs

Dogs with clinical Lyme disease are generally treated with antibiotics prescribed by a veterinarian. A commonly used treatment is a course lasting approximately four weeks, although the exact medication and treatment plan depend on the individual dog.

Veterinary treatment may also include supportive care when a dog has complications affecting the joints, kidneys, heart, or nervous system.

Many dogs with joint-related symptoms respond quickly to treatment, but some may experience persistent or recurring problems. Permanent joint damage can result in ongoing discomfort in some cases.

Do not give your dog leftover antibiotics or human medication without veterinary guidance. The correct drug, dose, duration, and monitoring depend on the dog’s condition.

Can Dogs Recover From Lyme Disease?

Many dogs with clinical Lyme disease improve substantially after appropriate veterinary treatment, particularly when the disease primarily affects the joints. MSD Veterinary Manual notes that most dogs with joint or leg symptoms improve rapidly after treatment.

However, recovery can vary. Dogs with significant kidney involvement or other complications may have a much more serious prognosis.

Can Lyme Disease Cause Kidney Problems in Dogs?

Yes. Kidney involvement is one of the most serious complications associated with Lyme disease in dogs.

A severe kidney condition associated with Lyme disease can lead to significant illness and may be fatal. Warning signs can include changes in appetite, vomiting, increased thirst or urination, weight loss, and marked lethargy.

Because kidney disease can progress rapidly, a dog showing concerning symptoms after possible tick exposure should be evaluated promptly by a veterinarian.

Is Lyme Disease Contagious Between Dogs?

Lyme disease is not normally spread directly from one dog to another through normal contact.

The important transmission route is an infected tick. However, dogs can transport ticks into households, potentially increasing the opportunity for those ticks to bite people or other animals.

How to Prevent Lyme Disease in Dogs

Tick prevention is one of the most important ways to reduce the risk of Lyme disease.

1. Use Veterinary-Recommended Tick Prevention

Ask your veterinarian about an appropriate tick-control product for your dog’s age, size, lifestyle, and geographic area.

Consistent use is important because occasional treatment may leave gaps in protection.

2. Check Your Dog for Ticks

After outdoor activities, inspect your dog carefully, particularly around:

• Ears
• Neck
• Head
• Between the toes
• Under the legs
• Groin
• Around the collar

Finding a tick early can help reduce the opportunity for disease transmission.

3. Remove Ticks Promptly

If you find an attached tick, remove it carefully with fine-tipped tweezers. Grip the tick close to the skin and pull steadily rather than squeezing its body.

4. Keep Your Yard Less Attractive to Ticks

Keeping grass short, removing excess leaf litter, and reducing dense vegetation around areas where your dog spends time can help reduce tick habitat.

5. Ask About Lyme Vaccination

Lyme vaccines for dogs are available, and vaccination may be recommended for dogs living in or regularly visiting areas where Lyme disease is common. Your veterinarian can determine whether vaccination is appropriate for your dog.

When Should You Take Your Dog to a Veterinarian?

Contact your veterinarian if your dog develops symptoms such as:

• Sudden or recurring lameness
• Swollen or painful joints
• Fever
• Loss of appetite
• Unusual tiredness
• Reluctance to walk or exercise
• Vomiting or other signs of illness
• Increased thirst or urination
• Neurological abnormalities

You should also tell your veterinarian if you recently found a tick on your dog or if your dog regularly spends time in areas where ticks are common.

Lyme Disease in Dogs vs. Other Tick-Borne Diseases

Lyme disease is only one of several diseases that ticks can transmit to dogs. Ehrlichiosis, anaplasmosis, and other tick-borne infections can cause overlapping symptoms.

For this reason, a dog with fever, lethargy, poor appetite, or lameness after tick exposure may need veterinary testing for more than one condition.

Frequently Asked Questions

Can a dog get Lyme disease from another dog?

No. Lyme disease is primarily transmitted through infected tick bites rather than direct dog-to-dog contact.

Can indoor dogs get Lyme disease?

Yes, if an infected tick enters the home and bites the dog. Dogs that spend time outdoors generally have greater exposure to ticks.

Can Lyme disease be fatal in dogs?

It can be, particularly when serious kidney complications develop. Most dogs with uncomplicated joint-related Lyme disease have a considerably better prognosis with appropriate veterinary treatment.

How long does Lyme disease treatment take in dogs?

Treatment commonly involves approximately four weeks of antibiotics, although the veterinarian determines the appropriate treatment for each dog.

Can a dog have Lyme disease without symptoms?

Yes. Many infected dogs show no obvious clinical signs. A positive antibody test therefore needs to be interpreted in the context of the dog’s symptoms and exposure history.

Can dogs spread Lyme disease to humans?

Dogs do not normally transmit Lyme disease directly to humans. However, they can carry infected ticks into the home, and those ticks can subsequently bite people.

Key Facts About Lyme Disease in Dogs

Lyme disease is an important tick-borne infection that can affect dogs, particularly those exposed to tick habitats. The most recognizable canine signs include fever, lethargy, loss of appetite, swollen or painful joints, and shifting lameness.

The best approach is prevention through consistent tick control, regular tick checks, prompt tick removal, and veterinary guidance about vaccination where appropriate.

If your dog develops symptoms following possible tick exposure, seek veterinary advice rather than trying to diagnose or treat the condition at home.

Medical disclaimer: This article is for educational purposes and is not a substitute for professional veterinary diagnosis or treatment.

Sources & References

1. MSD Veterinary Manual — Lyme Disease (Lyme Borreliosis) in Dogs
   Comprehensive veterinary information covering causes, symptoms, diagnosis, treatment, complications, and prevention.
2. MSD Veterinary Manual — Lyme Borreliosis in Animals
   Professional veterinary reference covering transmission, clinical signs, diagnosis, treatment, and prevention of Lyme borreliosis in dogs and other animals.
3. Companion Animal Parasite Council (CAPC) — Lyme Disease
   Veterinary parasite-control guidance covering tick transmission, diagnosis, treatment, vaccination, tick prevention, and disease risk.
4. Companion Animal Parasite Council — 2026 Annual Pet Parasite Forecasts
   Current information on canine Lyme disease and other vector-borne disease risks and geographic trends for 2026.
5. Companion Animal Parasite Council — Ixodes scapularis and Ixodes pacificus
   Information about black-legged ticks, year-round tick control, and Lyme disease prevention in dogs.