Stevens-Johnson Syndrome & Toxic Epidermal Necrolysis
SJS/TEN High-yield Verified · Sep 2026Stevens-Johnson syndrome and toxic epidermal necrolysis are acute, severe, T-cell–mediated cutaneous adverse reactions — usually to a medication — in which the epidermis and mucous membranes die and detach; SJS involves less than 10% of body surface area and TEN more than 30%.
SJS and TEN are one disease measured by how much skin detaches: under 10% of body surface area is SJS, 10–30% is overlap, over 30% is TEN. A flu-like prodrome, then painful targetoid or dusky patches, blisters and mucosal erosions, usually 4 to 28 days after starting antiepileptics, allopurinol, sulfonamide antibiotics or NSAIDs. The skin barrier fails like a burn — fluids, warmth, infection control and eye care decide the outcome.
What’s going wrong in the body
The normal physiology, where it fails, and why the body’s compensation backfires.
01 A drug-triggered T-cell attack that kills the epidermis
[SJS/TEN] "Stevens-Johnson syndrome and toxic epidermal necrolysis represent a severe T-cell–mediated type IV (delayed) hypersensitivity reaction." A drug is presented to cytotoxic T cells on the HLA (major histocompatibility) molecule; "The activated CD8+ T cells then trigger downstream production of cytokines and chemokines, as well as apoptosis of epidermal keratinocytes, through various pathways, including the Fas/Fas ligand (FasL) pathway, the perforin/granzyme pathway, and granulysin."
NLM: the drug causes "cytotoxic T cells and natural killer (NK) cells to release a substance called granulysin that destroys cells in the skin and mucous membranes. The death of these cells causes the blistering and peeling that is characteristic of SJS/TEN." Histology shows "extensive full-thickness epidermal necrosis with subsequent epidermal detachment."
Why HLA matters. "Studies suggest that the HLA-B gene variations associated with SJS/TEN cause the immune system to react abnormally to certain medications" — for example, "the HLA-B *1502 allele found in the Han Chinese population is highly associated with carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis." But "most people with genetic variations that increase the risk of SJS/TEN never develop the disease."
02 One spectrum, graded by detached skin
"Although Stevens-Johnson syndrome and toxic epidermal necrolysis were once thought to be separate conditions, they are now considered part of a continuum." "SJS affects less than 10% of the total body surface area, SJS and TEN overlap affects 10% to 30% of total body surface area, and TEN affects greater than 30% of total body surface area."
What counts. "BSA involved includes both epidermis that is detachable (positive Nikolsky sign) and epidermis that is already detached. Areas of erythema without evidence of detachment or impending detachment are not included." The Nikolsky sign is "epidermal detachment with gentle lateral pressure or traction" — but "Nikolsky sign is not pathognomonic for SJS/TEN alone, as it can be present in multiple diseases."
Why it behaves like a burn. "Because the skin normally acts as a protective barrier, extensive skin damage can lead to a dangerous loss of fluids and allow infections to develop." "Epidermal barrier breakdown can lead to homeostatic dysfunction, electrolyte derangement, hypothermia, dehydration, and/or sepsis." Massive cytokine release "may lead to major metabolic disturbances, including sepsis, multiorgan failure, and gastrointestinal tract hemorrhage."
03 Recognize early, stop the drug, support like a burn
Onset. "Most cases occur 4 to 28 days after initial exposure to the drug." "Most patients report a prodrome of influenza-like symptoms, such as malaise, fever, myalgias, and upper respiratory tract symptoms, preceding the rash by 1 to 21 days." FDA: the conditions "usually begin with flu-like symptoms, followed by rash, blistering, and detachment of the upper surface of the skin."
Red flags. "Red flags on initial examination include skin pain, prodromal symptoms and mucositis in relation to a rapidly developing extensive rash." "The hallmark feature of SJS or TEN is mucosal involvement." SJS and TEN "are medical emergencies that usually require hospitalization."
First moves. "Of these components, identification and cessation of the causative drug is most important." StatPearls, citing the Society of Dermatology Hospitalists guideline, says emergency care should focus on "discontinuation of the offending drug and early referral to a burn unit or intensive care unit experienced in treating such patients." Supportive care — fluids, warmth, wound and eye care, nutrition, infection surveillance — continues "until reepithelialization of the affected skin." "No proven effective treatment modality exists" among immunomodulators.
Causes & risk factors
Modifiable factors are teaching targets — the patient can act on them.
Signs & symptoms
Each finding tied to the mechanism that produces it — and the triage it calls for.
Diagnostics
Complications
Medications for this condition
Why each class is prescribed here — every card links to its full pharmacology page.
Common culprits — "lamotrigine, carbamazepine, phenytoin, valproic acid, phenobarbital." Tegretol boxed warning: SJS/TEN risk is "ABOUT 10 TIMES HIGHER" in some Asian countries; screen for HLA-B*1502 in at-risk ancestry before starting; over 90% of cases occur "within the first few months of treatment"; stop at the first rash. Lamictal boxed warning: serious rash in "0.3% to 0.8% in pediatric patients" and "0.08% to 0.3% in adults"; risk rises with valproate or exceeding the starting dose or escalation; nearly all cases "within 2 to 8 weeks"; "Do not restart LAMICTAL in patients who discontinued due to rash unless the potential benefits clearly outweigh the risks."
Culprit — trimethoprim-sulfamethoxazole. Bactrim: "should be discontinued at the first appearance of skin rash or any sign of a serious adverse reaction"; patients should "stop taking BACTRIM immediately" for rash, sore throat, fever, joint pain, cough, purpura or jaundice and contact their provider.
Culprit — allopurinol. "Discontinue Allopurinol Tablets permanently at the first appearance of skin rash or other signs which may indicate a hypersensitivity reaction." Risk "is largely confined to the first few months of therapy"; consider HLA-B*58:01 screening where prevalence is high.
Culprit — NSAIDs (oxicams; celecoxib). Celebrex: patients should "stop taking CELEBREX immediately if they develop any type of rash or fever"; it "is contraindicated in patients with previous serious skin reactions to NSAIDs." FDA: NSAIDs such as ibuprofen and naproxen "also carry the risk of causing serious skin reactions."
Controversial adjunct — not proven. "Systemic corticosteroids are commonly used to halt the progression of TEN. However, results from some studies linked corticosteroids to increased mortality incidence." They are associated "with increased risk of infection"; "The role of corticosteroids as monotherapy is still debated." Topical corticosteroid drops may be part of eye care (StatPearls, citing SDH).
Beyond medications
- Stop the culprit — and all nonessential drugs. "Withdrawal of the offending drug and all nonessential medications is critical, followed by hospitalization and supportive care."
- Burn unit or ICU. "Early transfer to a burn facility or intensive care unit with staff experienced in treating complex wounds, fluid resuscitation, and mechanical ventilation improves overall survival in these patients."
- Fluids — like a burn, but less. Requirements mirror burn patients "although fluid requirements are about 30% less in SJS/TEN patients than in burn patients with similar degrees of cutaneous involvement"; replacement "should be driven by urine output, with a goal of 0.5–1 mL/kg/h."
- Warmth. "The environment should be kept warm (30–32 °C)" due to "loss of thermoregulatory function of skin."
- Wound care. "Aseptic wound care is important to prevent secondary infection until reepithelialization." "Nonadhesive sterile dressings should be used to cover areas of skin erosions" (StatPearls, citing SDH). Debridement versus leaving detached skin in place as a biological dressing — "there is currently no consensus."
- Infection — culture, don't prophylax. "Prophylactic antibiotics are not recommended because they do not change survival rates"; "prompt use of antibiotics in the setting of clinical infection is likely critical."
- Nutrition. "Enteral feeding is superior to parenteral feeding because it decreases the risk of bacterial translocation. If the oral mucosa is significantly affected, a nasogastric tube may be used."
- Pain. "Pain control is extremely important to decrease patient distress. Opiates or patient-controlled analgesia can be used" (StatPearls, citing SDH). "Good wound care also reduces analgesic requirements."
- Eyes, mouth, genitals. Eye care "usually consists of topical lubricants, antibiotics, or corticosteroid drops"; "Topical estrogen is used to promote mucosal healing" in genitourinary involvement (StatPearls, citing SDH). Supportive-care bundles include oral, ocular and genitourinary care, stress-ulcer and DVT prophylaxis (Shah 2024, citing SDH).
Nursing considerations
The RN-specific layer — each action paired with the reason it matters.
How a real nurse thinks
The clinical-judgment loop, worked for a typical presentation — reasoning, not reference.
- 1 Recognize cues
A flu-like prodrome, then a painful dusky, blistering rash with a positive Nikolsky sign, mouth, eye and genital erosions, starting 3 weeks after allopurinol; tachycardia and borderline blood pressure; unable to drink.
- 2 Analyze cues
This pattern is SJS/TEN; about 8% detached/detachable skin puts him in the SJS range now, but the process can extend. Allopurinol fits the 4–28-day window; ibuprofen is also a possible culprit. Mucosal and eye involvement threaten airway, intake and vision; lost skin means fluid and heat loss and infection risk.
- 3 Prioritize
Stop the culprit drugs, protect the airway and circulation, and arrange burn-unit/ICU-level care and eye review.
- 4 Generate solutions
Hold allopurinol and ibuprofen and notify the provider; assess airway and swallowing; IV access with fluids titrated to urine output; warm the room; nonadhesive sterile dressings; analgesia; cultures; early ophthalmology consult; document allergy.
- 5 Take action
SBAR: 48-year-old started allopurinol 3 weeks ago, now fever, blistering targetoid rash about 8% BSA with Nikolsky sign, oral, ocular and genital erosions, HR 118, BP 104/66, poor oral intake. Suspected SJS. Allopurinol and ibuprofen held; requesting burn-unit/ICU referral, IV fluids and ophthalmology. Warm room and sterile dressings in place.
- 6 Evaluate
Urine output reaches 0.5–1 mL/kg/h on IV fluids, temperature is maintained, airway stays patent, and ophthalmology reviews both eyes. No new blisters by day 3; the reaction and culprit drug are recorded as allergies before transfer.
Scenario — you’re the nurse
Work each question before revealing the answer. Rationales explain the wrong options too.
A 48-year-old man with gout was started on allopurinol 3 weeks ago. For 2 days he has had fever, sore throat and aching; today he developed painful dark red patches on his chest and face that are now blistering, and his mouth and lips are so sore he cannot drink. His eyes are red and gritty.
Q1 Multiple choice What is the nurse’s first priority for this patient? - A. Stop allopurinol (and ibuprofen) and notify the provider
- B. Apply silver sulfadiazine cream to the blisters
- C. Start prophylactic IV antibiotics
- D. Give a test dose of allopurinol to confirm the cause
Reveal answer & rationale
Q2 Multiple choice About 8% of his body surface area is detached or detachable. How is this classified? - A. Stevens-Johnson syndrome
- B. SJS/TEN overlap
- C. Toxic epidermal necrolysis
- D. Cannot be classified until erythema is included
Reveal answer & rationale
Q3 Select all that apply Which interventions belong in his supportive care? Select all that apply. - A. Keep the room warm
- B. Titrate IV fluids to urine output
- C. Early ophthalmology consultation
- D. Nonadhesive sterile dressings with aseptic technique
- E. Give full burn-formula (Parkland) volumes regardless of urine output
- F. Enteral nutrition, by nasogastric tube if the mouth is too painful
Reveal answer & rationale
Q4 Multiple choice On day 4 his temperature suddenly drops to 35.6 °C and his heart rate rises to 130. What should the nurse suspect? - A. Expected healing response
- B. Sepsis — obtain cultures and notify the provider immediately
- C. Allergic reaction to the dressings
- D. Dehydration only — increase oral fluids
Reveal answer & rationale
Q5 Select all that apply Which statements belong in his discharge teaching? Select all that apply. - A. Never take allopurinol again
- B. Tell every health-care professional about this reaction
- C. A negative HLA test later would make allopurinol safe to restart
- D. Report new eye dryness, light sensitivity or vision change
- E. Mood changes and anxiety after SJS are common and treatable — report them
Reveal answer & rationale
Common questions
What causes stevens-johnson syndrome & toxic epidermal necrolysis?
Are SJS and TEN different diseases?
Which drugs cause SJS/TEN most often?
Why is SJS/TEN treated like a burn?
Do steroids cure SJS/TEN?
Why test for HLA-B*1502 before carbamazepine?
Sources
- Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis — StatPearls — StatPearls (NCBI Bookshelf)
- Shah H et al. Update on Stevens–Johnson Syndrome and Toxic Epidermal Necrolysis: Diagnosis and Management (Am J Clin Dermatol 2024, CC BY-NC 4.0) — PubMed Central
- Frantz R et al. Stevens–Johnson Syndrome and Toxic Epidermal Necrolysis: A Review of Diagnosis and Management (Medicina 2021, CC BY 4.0) — PubMed Central
- Stevens-Johnson syndrome/toxic epidermal necrolysis — MedlinePlus Genetics — National Library of Medicine
- TEGRETOL (carbamazepine) — FDA label — U.S. FDA / NLM DailyMed
- LAMICTAL (lamotrigine) — FDA label — U.S. FDA / NLM DailyMed
- Allopurinol Tablets (Dr. Reddy’s) — FDA label — U.S. FDA / NLM DailyMed
- BACTRIM (sulfamethoxazole and trimethoprim) — FDA label — U.S. FDA / NLM DailyMed
- CELEBREX (celecoxib) — FDA label — U.S. FDA / NLM DailyMed
- Questions and Answers: FDA warns of rare but serious skin reactions with acetaminophen — U.S. Food and Drug Administration
Reviewed by Hae Suk Lee, RN
Educational summary for nursing students. Scenarios are fictional teaching cases. Always verify against current guidelines and your institution's protocols before acting in practice. Not medical advice.