This is tough without seeing the rash. Look at our section on Lyme for good pictures of the typical rash. In general, the Lyme rash should be greater than 5 cm in diameter. It does not have the have the typical bullseye pattern and a bullseye pattern doesn’t always mean that it is Lyme disease.
About Alan Matsumoto, M.D.
Part-time Faculty, Division of Rheumatology
Johns Hopkins University