Lyme Disease in Dogs: Symptoms, Prevention & Treatment

How Dogs Get Lyme Disease

Lyme disease is transmitted exclusively through the bite of an infected black-legged tick, commonly called a deer tick. Critically, transmission isn’t instantaneous: research indicates the tick generally needs to remain attached for roughly 24 to 48 hours before the bacterium passes into the dog’s bloodstream, which is exactly why prompt tick checks and removal after outdoor time are such an effective prevention measure on their own. Ticks pick up the bacterium from infected wildlife, most often white-footed mice and other small rodents, then pass it along to the next host they bite, whether that’s a dog, a person, or another animal. Because these ticks are tiny, particularly in their nymph stage, and often bite in hard-to-see areas like between toes, in ears, or around the collar line, a bite can easily go completely unnoticed until symptoms, if they occur, prompt a vet visit weeks later.

Symptoms of Lyme Disease in Dogs

Shifting-leg lameness. One of the most characteristic signs: lameness that seems to move from one leg to another over days, caused by migrating joint inflammation.

Joint swelling and pain. Affected joints may be warm, swollen, and painful to the touch, sometimes accompanied by reluctance to move normally.

Fever and lethargy. A general sense of being unwell, reduced energy, and an elevated temperature often accompany the joint-related signs.

Reduced appetite. Some dogs eat less during an active flare-up of symptoms.

Swollen lymph nodes. Enlarged lymph nodes near the site of the tick bite or more generally throughout the body can occur.

No symptoms at all. Importantly, the majority of dogs exposed to Lyme disease never develop any clinical signs whatsoever, which is part of why routine testing, rather than waiting for symptoms, is often recommended in tick-endemic areas.

Lyme Nephritis: The Serious Complication

While most Lyme-related lameness resolves well with treatment, a small percentage of dogs develop a much more serious complication called Lyme nephritis, in which the immune response to the infection damages the kidneys. This tends to occur weeks to months after the initial tick bite and can progress quickly once it starts, sometimes leading to protein loss through the kidneys and, in severe cases, kidney failure. Signs to watch for include increased thirst and urination, vomiting, weight loss, and reduced appetite, particularly in a dog with a known history of tick exposure or a prior positive Lyme test. Because Lyme nephritis can be life-threatening and doesn’t always announce itself with obvious joint symptoms first, some veterinarians recommend periodic urine testing for protein loss in dogs from high-risk, tick-endemic regions, even without other symptoms present.

Diagnosis and Treatment

Diagnosis typically starts with a blood test that screens for exposure to several tick-borne diseases at once, often performed as part of routine annual wellness bloodwork in endemic areas. A positive result combined with consistent clinical signs generally leads to a course of antibiotics, typically lasting several weeks, which most dogs respond well to, often showing improved comfort and mobility within days of starting treatment. It’s worth understanding that a positive antibody test alone, without symptoms, doesn’t automatically mean treatment is necessary; this is a nuanced discussion many veterinarians have with owners, since antibodies can persist even after a past exposure has resolved on its own. For dogs that do develop Lyme nephritis, treatment is considerably more involved, potentially including specialized kidney-support diets, medications to manage protein loss, and closer monitoring, reflecting the more serious nature of this complication.

Preventing Lyme Disease

Other Tick-Borne Diseases to Know About

Lyme disease is the most commonly discussed tick-borne illness, but the same ticks, and sometimes different tick species entirely, can transmit several other diseases worth knowing about, since prevention strategies overlap significantly. Anaplasmosis and Ehrlichiosis are both bacterial infections transmitted by ticks that can cause symptoms similar to Lyme disease, fever, lethargy, joint pain, and sometimes more serious blood-related complications, and are often screened for on the same combination blood test used for Lyme disease. Rocky Mountain spotted fever, transmitted by a different tick species, can cause more severe systemic illness including fever, lethargy and sometimes neurological signs. Babesiosis, transmitted by ticks in certain regions, affects red blood cells and can cause significant anemia. Because these diseases share the same prevention strategy, consistent tick control, prompt tick removal, and awareness of your regional risk, a veterinarian discussing Lyme disease prevention with you is often addressing this whole category of tick-borne illness at once rather than Lyme disease in isolation. This is also why a combination screening test, rather than a Lyme-specific test alone, is frequently used during annual wellness visits in tick-endemic areas.

Tick Removal: Doing It Correctly Matters

Since transmission risk increases the longer a tick remains attached, knowing how to remove one properly and promptly is a genuinely practical skill for any dog owner in a tick-prone area. Using fine-tipped tweezers or a tick removal tool, grasp the tick as close to the dog’s skin as possible, avoiding squeezing the tick’s body, which can potentially push infectious material into the bite wound. Pull straight upward with steady, even pressure rather than twisting or jerking, which can leave mouthparts embedded in the skin. After removal, clean the bite site with antiseptic and monitor it over the following days for any redness, swelling, or discharge that might suggest local infection. Avoid folk remedies like burning a tick or covering it with petroleum jelly to try to make it detach on its own; these methods are not recommended and can actually increase the risk of the tick regurgitating infectious material into the wound. If you’re ever unsure about proper removal, or if part of the tick appears to remain embedded, a veterinary visit for professional removal is a reasonable, low-risk option.

Lyme Disease Risk While Traveling With Your Dog

Owners often think about tick risk only in the context of their home region, but traveling with a dog to a different area can meaningfully change exposure risk in ways worth planning for in advance. If you’re heading somewhere with a known higher tick population or Lyme prevalence than your home area, confirming your dog’s current tick preventive is genuinely up to date, not just applied recently but still within its effective window, is a simple pre-trip check. Packing a tick removal tool and doing more frequent, deliberate tick checks during and after outdoor activity in an unfamiliar high-risk area adds an extra layer of protection beyond routine prevention alone. If your travel plans are seasonal or occasional rather than a permanent move, discussing with your veterinarian whether the Lyme vaccine makes sense given your specific travel pattern, rather than only your home region’s baseline risk, is a reasonable conversation to have well before the trip rather than as an afterthought.

Frequently Asked Questions

By Dr. Zahid Afzal, DVM — General Veterinary Hospital, Lahore. This article is for general education and does not replace a full physical examination, blood testing or personalized prevention and treatment plan from your own veterinarian.