A 50-year-old client on day 8 of TMP-SMX develops fever, malaise, and a painful spreading rash with target lesions, mucosal blisters in the mouth and conjunctivae, and skin sloughing on light pressure. Which is the priority nursing action?

Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions on a continuum (SJS less than 10 percent, SJS/TEN overlap 10-30 percent, TEN over 30 percent body surface area sloughing). Common triggers: sulfonamides, allopurinol, anticonvulsants (carbamazepine, lamotrigine, phenytoin), nevirapine, NSAIDs, and others. Onset typically days to weeks after starting the drug. Presentation: prodromal fever, malaise, sore throat, conjunctivitis; then painful erythematous to dusky macules with target lesions, blistering, positive Nikolsky sign (skin slides off with light pressure), mucosal involvement of mouth, eyes, genitals. Mortality is high — TEN up to 30 percent. Standard nursing response: (1) immediately stop the offending drug and any cross-reactive drugs; (2) emergency transfer to a burn or ICU unit because the loss of skin barrier resembles severe burns; (3) airway protection, fluid and electrolyte management, nutrition, infection prevention, pain control, eye care to prevent corneal scarring; (4) consults with dermatology, ophthalmology, possibly intensive care and burn surgery; (5) document the drug as a permanent allergy in the chart and educate the patient and family to avoid sulfa-containing drugs forever; medical alert bracelet recommended. Continuing the drug, redosing, antihistamine alone, or topical ointment alone are unsafe and life-threatening.

SJS/TEN is a dermatologic emergency. Stop drug, transfer to burn/ICU, protect skin and airway, lifelong allergy label.