Lyme disease is an infection caused by bacteria transmitted to humans through tick bites. It is a complex illness that can affect multiple systems in the body and may last from a few weeks to several years. While it can become serious, Lyme disease is treatable with appropriate medications, and there are many preventive measures available.

If you live in an area where Lyme disease is common and begin to experience symptoms, it’s important to contact your healthcare provider. Many people do not realize they’ve been bitten until symptoms appear. Medical evaluation and early testing can help prevent complications and allow for timely treatment.

Symptoms of Lyme Disease

When not treated promptly, Lyme disease typically progresses through three stages: early localized, early disseminated, and late-stage Lyme disease.

Early Localized Stage

This stage generally appears between 3 to 30 days after a tick bite. Symptoms include low-grade fever, body aches, swollen lymph nodes, and the hallmark erythema migrans (EM) rash. EM starts at the site of the bite and expands outward, often forming a “bull’s eye” pattern. This rash appears in the majority of Lyme cases and typically shows up about a week after the bite.

It’s important to distinguish EM from other types of rashes. A small red spot that appears right after removing a tick and doesn’t expand is likely caused by tick saliva, not Lyme disease.

Early Disseminated Stage

This phase begins days to months after the initial infection and can last several months. Symptoms may include:

  • Fever

  • Fatigue

  • Headache

  • Muscle and joint pain

  • Chest pain and palpitations

  • Shortness of breath

  • Dizziness

  • Double vision

  • Neurological symptoms like encephalopathy or meningitis

  • Facial palsy affecting one or both sides of the face

In some cases, Lyme disease affects the heart, a condition called Lyme carditis, which can disrupt normal heart rhythms. With proper treatment, recovery from Lyme carditis usually occurs within a few weeks.

Late Stage

The final stage of Lyme disease often develops within a year but can take several years to appear. A key sign is arthritis, especially in the knees, although other joints may be involved. Neurological symptoms such as cognitive difficulties, facial palsy, and meningitis are also possible.

Causes

Lyme disease is caused by the bacteria Borrelia burgdorferi and, in some cases, Borrelia mayonii. These bacteria are carried by black-legged ticks (deer ticks) and can be transmitted through their bites.

While Lyme disease can occur in many regions, it is most common in the northeastern U.S., Minnesota, and Wisconsin. The majority of cases occur from late spring through early fall.

After entering the body, the bacteria spread from the bite site, sometimes causing an EM rash. As the infection moves through the body, it may trigger symptoms in joints, the nervous system, and other areas.

Risk Factors

You may be at higher risk of Lyme disease if you:

  • Hike or walk through wooded or grassy areas

  • Work outdoors

  • Live in regions with a high number of cases

  • Are female (some studies suggest higher risk in females)

Not all tick bites result in Lyme disease. A tick usually must be attached for at least 36–48 hours to transmit the bacteria.

Diagnosis

To determine if you have Lyme disease, your healthcare provider will ask about your symptoms, travel history, outdoor activities, and any potential tick exposure. They may begin treatment immediately if your symptoms are consistent with Lyme disease—particularly if you have the EM rash—even without lab tests.

In many cases, especially when symptoms are nonspecific or if the tick bite is not recalled, blood tests may be ordered. These tests look for antibodies your body produces to fight infection. However, antibodies may not appear until a few weeks after infection, which can result in a false negative if testing is done too early. False positives can also occur, particularly if you have another infection or autoimmune disease.

Treatment

Lyme disease is treated with antibiotics, which are highly effective when administered early. The specific medication, dosage, and route (oral or IV) will depend on factors like your age and the severity or location of your symptoms.

Common antibiotics include:

  • Doxycycline

  • Amoxicillin

  • Cefuroxime

  • Ceftriaxone

In certain cases, such as with Lyme carditis, additional interventions like a temporary pacemaker may be needed to manage heart issues until the antibiotics take effect.

How to Prevent Lyme Disease

The best way to avoid Lyme disease is by preventing tick bites. You can reduce your risk by:

  • Using tick repellents such as picaridin, and reading labels for safe usage

  • Wearing long sleeves and tucking pants into socks when walking in wooded or grassy areas

  • Choosing light-colored clothing to easily spot ticks

  • Staying on trails and avoiding tall grass, leaf piles, and dense bushes

  • Speaking with your vet about tick prevention for pets

Since ticks need at least 36–48 hours of attachment to transmit the bacteria, checking your body after outdoor activity and removing ticks properly can greatly reduce your risk. Use fine-tipped tweezers to remove ticks close to the skin’s surface. Pull upward with steady pressure, and clean the area thoroughly after removal.

Complications

A small number of people may experience symptoms such as pain, fatigue, or mental fog that persist for more than six months after treatment. This is known as post-treatment Lyme disease syndrome (PTLDS).

The cause of PTLDS is not fully understood. Some experts believe it’s an autoimmune reaction triggered by the original infection, while others think the symptoms may not be related to Lyme disease at all. If you believe you have PTLDS, consult your provider for further evaluation.

Outlook

Most people diagnosed with Lyme disease recover fully with a course of antibiotics. Treatment duration can range from a few days to several weeks, depending on the stage and severity of the illness. Early detection and prompt treatment help prevent the disease from advancing.

People with PTLDS may continue to experience symptoms for months. While there is currently no cure, healthcare providers can help manage these symptoms. In most cases, symptoms improve gradually over time.