What causes Stevens-Johnson syndrome?

This condition is an intense reaction in which the immune system damages skin and the moist linings of the body. It can begin after starting a new medicine, changing a dose, or occasionally after an infection. Medicines associated with severe drug eruptions include some treatments for seizures, infections, inflammation, or pain, but the responsible product cannot be identified from the rash alone.

Early symptoms may resemble a flu-like illness, followed by skin pain, widespread dusky or red patches, blisters, and peeling. The eyes, mouth, lips, genitals, and airways may also be affected. Stevens-Johnson syndrome belongs to the same severe drug-reaction spectrum as toxic epidermal necrolysis and requires hospital-level assessment.

Treat a rapidly worsening blistering or peeling rash as an emergency. Bring every medicine packet, supplement, and recent prescription information to the emergency team, including products started recently and medicines taken only occasionally. Do not restart a suspected medicine unless a specialist who knows the reaction tells you to do so.

Hospital care may include stopping the responsible medicine, protecting damaged skin, replacing fluids, controlling pain, and checking the eyes, mouth, lungs, and other affected areas. Keep a clear record of the suspected drug and reaction for future clinicians.

Go to an emergency department immediately for skin pain with a spreading rash, blisters, peeling, sores in the mouth or eyes, difficulty swallowing, breathing problems, faintness, or fever with a new rash. Do not wait for a routine dermatology appointment; this reaction can worsen quickly and may need specialist monitoring.

Which medicine or infection could have triggered this reaction? Which products must I avoid in the future? Should I carry a written drug-allergy record? Do my eyes or other mucosal areas need specialist review?