If left untreated, Lyme disease can lead to a wide range of more serious health problems
as the infection spreads to other parts of the body. These complications can occur days
to months after the initial tick bite.
One of the common problems is arthritis, particularly affecting the knees and other large
joints, causing severe pain and swelling. The infection can also affect the nervous
system, leading to issues such as severe headaches and neck stiffness, facial palsy
(drooping on one or both sides of the face), nerve pain, shooting pains, numbness, or
tingling in the hands or feet. In some cases, untreated Lyme disease can cause more
serious neurological problems like inflammation of the brain and spinal cord (meningitis
or encephalitis).
Furthermore, the heart can be affected, leading to Lyme carditis, which may cause heart
palpitations or an irregular heartbeat. Other potential symptoms include additional
erythema migrans (EM) rashes on other areas of the body, and episodes of dizziness or
shortness of breath. In rare instances, untreated Lyme disease can also cause visual
disturbances.