What Lyme Disease Rashes (Erythema Migrans) Look Like

Over 70 percent of people with Lyme disease develop an erythema migrans rash. Certain features set it apart from other skin lesions.

CDC's one-page poster, The Many Forms of Lyme Disease Rashes (PDF), shows them side by side.

Forms of erythema migrans

The "bull's-eye" or target form: a circular, expanding rash. CDC.

The rash can also appear as:

• an expanding lesion with a crust in the centre, here on the chest;
• an early, expanding rash with a nodule;
• many lesions with dusky centres, in early disseminated Lyme disease;
• a red, expanding, oval-shaped plaque on the trunk;
• a circular, expanding rash that clears in the centre;
• a bluish rash that does not clear in the centre;
• an expanding lesion that does not clear in the centre, on the back of the knee;
• a red-blue lesion with some clearing in the centre, on the back of the knee.

Rashes that can look like it

• Insect bite hypersensitivity: a large, itchy rash caused by an allergic reaction to an insect bite.
• Fixed drug reaction: a skin condition that appears up to two weeks after someone takes a medicine, and comes back in the same place every time they take that medicine.
• Ringworm (tinea corporis): a common skin infection caused by a fungus, named for the ring-shaped rash it can cause, usually red and itchy with raised edges.
• Pityriasis rosea: a rash with no known cause that can be round or oval, pink and scaly with a raised border, and sometimes itches. Patches larger than the one in CDC's photograph are also common.
• Granuloma annulare: reddish bumps on the skin arranged in a circle or ring.
• Urticaria multiforme: also known as hives, often caused by an allergic reaction to food, an infection or a medicine; it may burn or itch.

Sources

• Centers for Disease Control and Prevention, "Lyme Disease Rashes." https://www.cdc.gov/lyme/signs-symptoms/lyme-disease-rashes.html
• CDC's photographs of the other rashes, credited to individual photographers or reprinted from a journal with its publisher's permission, are not reproduced here.