Stevens-Johnson Syndrome: What Every GP Needs to Know in 2025

Stevens-Johnson Syndrome (SJS) is a rare but life-threatening skin reaction that can appear in general practice - often suddenly, often deceptively. For GPs, registrars, and IMGs preparing for RACGP or ACRRM exams, it’s a condition you must be able to recognise early.

At PassGP, we regularly feature SJS in KFP and CCE scenarios because it tests your ability to link rash + systemic signs + recent medications with urgent referral decisions.

A/Prof George Eskander, PassGP’s Chief Examiner, emphasises:

“SJS isn’t rare in exams - it’s rare in life. That’s why it’s a favourite case. GPs need to think fast, ask the right questions, and refer early.”

What Is Stevens-Johnson Syndrome?

Stevens-Johnson Syndrome is a severe mucocutaneous reaction, usually triggered by a medication or infection. It involves:

• Widespread skin blistering
• Mucosal involvement (oral, ocular, genital)
• Systemic symptoms: fever, malaise, myalgia

It sits on a spectrum with Toxic Epidermal Necrolysis (TEN) - a more severe variant where >30% of the body surface is affected.

Common Triggers in General Practice

Most common drugs associated with SJS:

• Anticonvulsants: carbamazepine, lamotrigine, phenytoin
• Sulphonamide antibiotics: trimethoprim-sulfamethoxazole
• Allopurinol
• NSAIDs: especially oxicam derivatives

Most reactions occur within 1–3 weeks of starting the medication. Always ask:

“Have you recently started or restarted any new medications?”

 Clinical Features You Must Recognise

It often starts as a flu-like illness before the rash appears - leading to missed diagnoses in early stages.

What Should GPs Do?

Immediate action is critical. This is not a “watch and wait” rash.

1. Stop the suspected medication
2. Refer to ED immediately - do not delay
3. Call ahead - many hospitals have burns/dermatology protocols
4. Document suspected drug and time of exposure
5. Warn about recurrence risk - even small doses can be fatal next time

 Investigations (Hospital Setting)

• FBC, CRP, renal/liver function
• Blood cultures
• Skin biopsy (if uncertain)
• Ophthalmology and urology input (mucosal involvement)

 Why It’s an Exam Favourite (CCE & KFP)

SJS comes up often in KFP and CCE because it challenges your ability to:

• Take a focused red flag history (new meds, systemic signs)
• Differentiate from benign viral exanthems
• Make a clear and immediate escalation decision
• Know your hospital referral protocols

At PassGP, we include case-based scenarios that help registrars:

• Identify the correct next step (referral)
• Avoid unsafe options (e.g., prescribing steroids in community)
• Explain risks clearly to patients

 Model CCE Example (From PassGP)

You are a GP registrar. A 25-year-old man presents with fever, sore throat, and painful red rash that began on his trunk and has now spread to his arms and face. He began lamotrigine 2 weeks ago. His lips are cracked and bleeding, and he reports painful urination.

 Expected candidate actions:

• Ask about new medications
• Identify mucosal involvement
• Recognise red flags (skin peeling, pain > itch)
• Refer to emergency department immediately

Final Advice from A/Prof Eskander

“Any patient with systemic illness, rash, and mucosal symptoms deserves a second look. When in doubt - refer.”

 Want to Practise SJS in an Exam Setting?

PassGP’s KFP and CCE cases:

• Include SJS differentials and referrals
• Highlight unsafe vs safe options
• Provide video model answers with clinical reasoning

Start your free trial today at PassGP and learn from former National Lead Examiners who’ve seen it all.