What should you know about erythema nodosum not going away?

Erythema nodosum causes tender, warm lumps, usually over the shins. The skin may look red or bruised as the inflammation changes. A lump can take several weeks to fade, and soreness may outlast the visible redness. Ongoing or returning lesions can mean that the initial trigger is still active, that a medicine is contributing, or that another condition is producing similar-looking lumps. Possible triggers include an infection, inflammatory bowel disease, sarcoidosis, or a drug reaction, although a cause is not always found. Persistent symptoms do not by themselves identify the cause, so a clinician may review your history, medicines, recent illness, joint symptoms, bowel symptoms, and other skin changes.

Arrange an appointment if the lumps are not gradually improving, keep appearing, or interfere with walking or sleep. Until you are assessed, rest the affected legs when they are painful, elevate them when practical, and use a cool compress wrapped in cloth for comfort. Do not stop a prescribed medicine without advice; take a list of medicines and supplements to the appointment, including anything started shortly before the rash. Note when each lump appeared, whether it is changing colour or size, and whether you have fever, sore joints, cough, abdominal pain, or altered bowel habits. Treatment depends on the cause and may include addressing an infection or inflammatory condition, reviewing a medicine, and symptom relief. In selected cases, a clinician may discuss [Oral Corticosteroid Treatment](/treatments/medical-dermatology/oral-corticosteroid-therapy/).

Seek urgent medical help for rapidly increasing swelling, severe pain, a high fever, marked weakness, trouble breathing, chest pain, facial swelling, or signs of a serious allergic reaction. Prompt review is also appropriate if one leg becomes suddenly swollen and painful, if the skin becomes very hot with spreading redness, or if you cannot bear weight. These features can point to a problem needing faster assessment and should not be explained away as erythema nodosum without examination.

Ask whether the appearance still fits erythema nodosum, whether any medicine or recent infection could be a trigger, and whether your joint, chest, or bowel symptoms change the evaluation. You can also ask which comfort measures are suitable for you, what signs should prompt an earlier review, and whether a dermatologist or another specialist should be involved.