Antibiotics and Stevens–Johnson syndrome

Do not take another dose while arranging urgent assessment. Bring the medicine packet, prescription, and a list of everything recently taken, including non-prescription medicines and supplements.

Stevens–Johnson syndrome, often shortened to SJS, is a rare but severe immune reaction that damages the skin and moist linings of the body. It can follow a medicine, including some antibiotics, although an ordinary antibiotic rash is much more common.

Early illness can resemble flu, with fever, marked tiredness, sore throat, burning eyes, or body aches. A tender red or dusky rash may then spread, blister, and peel. Painful ulcers can affect eating, drinking, urination, or vision. The combination of skin pain and involvement of the mouth or eyes is particularly concerning.

Call emergency services or go to an emergency department; this reaction cannot be assessed safely through home monitoring. Do not drive yourself if you feel faint, confused, or very unwell. Avoid applying new creams or taking extra medicines to suppress the rash unless an emergency clinician advises them.

After assessment, ensure the suspected medicine and reaction are recorded clearly in your medical and pharmacy records. A clinician may advise avoiding the same drug and closely related medicines. Keep the exact generic and brand names available rather than relying on the broad label ‘antibiotic allergy’.

Treat a new rash with blisters, peeling, widespread skin tenderness, facial swelling, eye pain, light sensitivity, mouth ulcers, genital sores, breathing difficulty, or trouble swallowing as an emergency, particularly after starting a medicine. A rapidly worsening rash or feeling severely ill also warrants immediate help.

A mild rash without these features still needs prompt medical advice before the next antibiotic dose. Photographs taken as the rash changes may help the clinical assessment, but taking them must not delay care.

Ask which medicine is suspected, whether related drugs should be avoided, what wording belongs in your allergy record, and whether you need follow-up with dermatology, ophthalmology, or an allergy specialist. Confirm what infection still requires treatment and which alternative can be used safely.