Summary

• A mild, self-limiting, potentially recurring mucocutaneous inflammatory condition.
• Characterised by target lesions that resemble a bull's eye. These usually erupt over 24 to 48 hours and last for 1 to 2 weeks.
• Typically presents in a symmetrical distribution of lesions over the dorsal surfaces of the extensor extremities with minimal mucous membrane involvement.
• Generally related to infectious diseases and not drug exposure. The most commonly associated infections are herpes simplex virus and Mycoplasma pneumoniae. Other associated infections include hepatitis B, Epstein-Barr virus, cytomegalovirus, histoplasmosis (with concomitant erythema nodosum), orf (parapox virus that can be transmitted from sheep or goats to humans), coccidiodomycosis, Kawasaki disease, and gardnerella.
• Associated drugs include aminopenicillins, docetaxel, tumour necrosis factor (TNF)-alpha inibitors, antimalarials, anticonvulsants, and lidocaine injections. Statin medications have been associated with photo-induced lesions. Hepatitis B vaccine and allergic response to contact allergens have also been known to elicit the disorder.
• Supportive care and treatment of underlying infection remain the mainstay of therapy.