Lyme Disease

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Since only a small number of deer tick bites actually lead to Lyme disease, you don't need to see a doctor unless you develop symptoms. If you do, contact your doctor right away. He or she can determine whether these symptoms might be caused by a tick-borne disease and whether antibiotics will be needed. Even if your initial symptoms disappear on their own, you should still consult a doctor since Lyme disease may recur as a more generalized infection.

The onset of symptoms can occur within three to 30 days of a tick bite. If the infection goes untreated with antibiotics, symptoms can progress to chronic joint pain, muscle weakness, and neurological problems in a small number of people.

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For most people, the first symptom of Lyme disease is a telltale red rash known as erythema migrans. It starts as a small red spot that expands over a period of days or weeks, forming a circular, triangular, or oval-shaped rash. Sometimes the rash resembles a bull's eye because it appears as a red ring surrounding a central clear area. The rash, which can range in size from the diameter of a dime to the entire width of a person's back, appears within one to four weeks of a tick bite, usually occurring at the site of the bite. If untreated, the rash may disappear. The rash then might eventually reappear at different sites on the body. EM might be accompanied by symptoms such as fever, headache, stiff neck, body aches, and fatigue. These flulike symptoms might resemble those of common viral infections and usually resolve within days or a few weeks.


After several weeks to months of being infected with the bacteria, some people not treated with antibiotics develop recurrent attacks of painful swollen joints that last anywhere from a few days to a few months. The arthritis usually affects weight-bearing joints, most commonly the knee. About 10 percent to 20 percent of untreated patients may go on to develop chronic arthritis.

Neurological Symptoms

Lyme disease can affect the nervous system, causing symptoms such as stiff neck and severe headache (meningitis), temporary paralysis of facial muscles (Bell's palsy), numbness, pain or weakness in the limbs, and poor motor coordination. More subtle changes—such as memory loss, difficulty with concentration, and a change in mood or sleeping habits—have also been associated with Lyme disease but are not definitely proven to be caused by it.

Heart Problems

Approximately 1 in 20 untreated Lyme disease patients develops heart problems, such as an irregular, slow heartbeat, which can be signaled by dizziness or shortness of breath. These symptoms might persist for a few days or weeks before resolving.

Other Symptoms

Less common symptoms of Lyme disease are eye inflammation, hepatitis, and severe fatigue, although none of these problems is likely to appear without the presence of other Lyme disease symptoms.

Last reviewed on 10/03/2007

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