Viral Exanthems & Cutaneous Viral Infections — Topic Test

A 38-year-old woman from a leprosy-endemic area presents with sudden crops of tender, erythematous subcutaneous nodules with fever, malaise and arthralgia, two months after starting multidrug therapy for lepromatous leprosy. Histology shows neutrophilic infiltration with vasculitis. What is the drug of choice for this reaction?