Erythema Multiforme vs Stevens-Johnson Syndrome

Erythema multiforme often appears as fairly well-defined target lesions, commonly on the hands, arms, legs or face. It may involve the mouth but is often less extensive. Stevens-Johnson syndrome can begin with fever, feeling unwell and tender skin, followed by dusky or blistering areas that spread. The lips, mouth, eyes or genitals may become sore or eroded. A drug reaction is one possible trigger, though infections and other causes can also be relevant. These conditions can overlap in appearance, so a diagnosis cannot safely be made from a photograph alone.

If a new rash began after a medicine, record the name, dose and first date taken, including non-prescription products. Do not restart a suspected medicine unless the treating clinician specifically tells you to. Keep the skin clean, avoid rubbing blisters, and take urgent medical advice if the rash is spreading or painful. Treatment may include supervised supportive care and, in selected situations, medicines such as oral corticosteroids; the choice depends on the examination and suspected cause.

Seek emergency care for skin pain with a rapidly spreading rash, blisters or peeling, sores in the mouth or eyes, difficulty swallowing, breathing trouble, faintness, or fever with marked illness. Stevens-Johnson syndrome can affect fluid balance, the eyes and internal organs, so waiting for a routine appointment is unsafe when these features appear.

Could this be erythema multiforme, a drug rash or Stevens-Johnson syndrome? Which medicines and supplements should I avoid? Do my eyes or mouth need specialist review? What symptoms should make me return immediately?