Rituximab-induced serum sickness in pemphigus vulgaris

Rituximab is a b-cell depleting monoclonal antibody. its use in autoimmune blistering disorders has gained popularity in the past few years. its off-label use in severe and recalcitrant pemphigus vulgaris has been proved beneficial. serum sickness is a type-iii hypersensitivity reaction that could be seen after administration of biological immunotherapy like rituximab. it is seen 10–14 days after the 1st exposure and clinically presents as fever, maculopapular rash, and arthralgia. serum sickness with rituximab has not been reported frequently in pemphigus vulgaris patients. hence, we report a case of rituximab-induced serum sickness in a patient of pemphigus vulgaris.