Lyme arthritis is a late symptom of Lyme disease. It most commonly affects the knee and causes noticeable joint pain, swelling, and warmth. Lyme arthritis can be treated with antibiotics.

Lyme disease is a bacterial infection that’s spread through the bite of certain types of ticks. Researchers estimate that roughly 476,000 people are diagnosed and treated for Lyme disease each year in the United States.

When left untreated, Lyme disease can lead to a variety of late signs and symptoms. One of these is Lyme arthritis, which can lead to permanent joint damage. Read on to learn more about this late effect of Lyme disease.

Lyme disease is caused by the bacteria Borrelia burgdorferi. This bacteria can be found in the saliva of certain types of ticks, specifically deer ticks, that have been infected. It can be transmitted to humans through tick bites.

B. burgdorferi bacteria spread to the joints and surrounding tissues early on. However, while joint aches may happen in the early stages of infection, Lyme arthritis occurs in the later stages, typically after months have passed.

Lyme arthritis causes intense levels of inflammation in your joints. Over time, this can lead to permanent joint damage.

Risk factors

You’re at an increased risk for Lyme disease and Lyme arthritis if you live in an area where ticks capable of spreading Lyme disease are prevalent. As of 2022, this includes the northeastern, mid-Atlantic, and north-central United States.

People who work outdoors, such as in the forestry, construction, or landscaping industries, are at a higher risk. Those who spend a lot of time outdoors, such as gardening, hiking, or camping, are also at a higher risk for tick bites.

Generally speaking, the most common time to be bitten by an infected tick is in the spring through fall. These are the times ticks are most active.

Lyme arthritis can affect one or several joints. The knees are the most commonly impacted, but Lyme arthritis can also occur in other joints like the:

  • shoulder
  • hip
  • elbow
  • ankle
  • wrist
  • jaw

Lyme arthritis typically comes on in the months after you get Lyme disease. Symptoms include joints that are:

If left untreated, Lyme arthritis can lead to persistent or recurring flares of joint swelling and pain. These flares may last from weeks to months.

The main complication of Lyme arthritis is permanent joint damage. This can lead to joint pain and reduced range of motion that can impact daily activities and quality of life.

Untreated Lyme disease can also lead to other health problems, such as:

Many people who get Lyme disease aren’t aware that they’ve been bitten by a tick. However, in 70–80% of people, the characteristic bullseye rash associated with Lyme disease develops. See a doctor if you notice this rash.

Because some people don’t develop this rash, it’s still important to see a doctor if you have any symptoms of Lyme disease and any of the following are true:

  • you know you’ve recently been bitten by a tick
  • you live in an area where Lyme disease is common
  • you’ve recently traveled in an area where Lyme disease is common

It’s also a good rule of thumb to make an appointment with a doctor to discuss any joint swelling or pain that’s new, severe, or concerning.

If you develop symptoms of Lyme arthritis, a doctor will first start by getting your medical history and doing a physical exam, during which they’ll evaluate the affected joints.

If your doctor suspects that you have Lyme arthritis, a two-step antibody-based testing protocol can be used to diagnose Lyme disease. These tests use a blood sample and are very sensitive in people with Lyme arthritis.

Because Lyme arthritis can be similar to other types of arthritis, such as rheumatoid arthritis (RA) and septic arthritis, your doctor may order tests to rule such conditions out. Some examples include:

Lyme arthritis is treated with a 28-day course of oral antibiotics. According to the Centers for Disease Control and Prevention (CDC), the following regimens may be used for adults:

The same antibiotics may be used in children with Lyme arthritis as well. However, the dosage is adjusted based on age and body weight.

During treatment, over-the-counter medications like nonsteroidal anti-inflammatory drugs (NSAIDs) can be used to help with pain and inflammation. If severe joint damage has occurred, physical therapy may be recommended as a part of recovery.

When treatment is received, the outlook for most people with Lyme disease is excellent. Antibiotics help to clear the infection, reducing inflammation and preventing further joint damage.

However, it’s important to remember that Lyme arthritis can lead to lasting joint damage. This can impact joint function, reduce your ability to do certain activities, and lower quality of life.

Because of this, if you’re experiencing symptoms of Lyme arthritis, it’s important to see a doctor. While your symptoms may not be due to Lyme disease, they may be happening due to another medical condition that needs to be addressed.

You can find the answers to some more frequently asked questions about Lyme arthritis below.

Does arthritis from Lyme disease go away?

Lyme disease, which causes Lyme arthritis, can be effectively treated with antibiotics. However, any joint damage caused by Lyme arthritis will remain.

What are the top three severe symptoms of Lyme disease?

Three examples of severe Lyme disease symptoms include heart problems, neurological issues, and meningitis-like symptoms. These are all late signs and symptoms of Lyme disease.

What’s the difference between Lyme arthritis and rheumatoid arthritis?

The main difference between Lyme arthritis and rheumatoid arthritis is the cause. Lyme arthritis is caused by Lyme disease, a bacterial infection. Rheumatoid arthritis is an autoimmune condition where your immune system mistakenly attacks joint tissue.

Lyme disease may increase your risk of rheumatoid arthritis. A 2017 study details 30 people who went on to develop inflammatory arthritis, including rheumatoid arthritis, a median of 4 months after a Lyme disease diagnosis.

Lyme arthritis is caused by the bacterial infection Lyme disease. It can cause swelling, pain, and warmth in the affected joints and most often occurs in the knee. If left untreated, Lyme arthritis can cause permanent joint damage.

A doctor can effectively treat Lyme arthritis with a course of antibiotics. Lyme disease can also be prevented by taking steps to lower your risk of tick bites.