Nodular eruptions as a rare complication of botulinum neurotoxin type-A : case series and review of literature

Nodular eruption after botulinum neurotoxin type-A (BoNT-A) treatment is exceedingly rare, and the pathogenesis is poorly understood. This case series reports three patients that developed nodular eruptions following administration of Botox® (onabotulinum neurotoxin type A (ONA) injections). These patients had undergone multiple treatments before and after development of the eruptions which were uneventful. In addition to this, we have reviewed the published literature regarding this condition and have compared and contrasted the similarities and differences with regards to the clinical presentation and treatment with our patient cohort. This case series aims to raise awareness of this rare condition, its importance in relation to patient consent and provides a simplified management approach based on our experience. Further evaluation is needed to determine treatment consensus but conducting such research may prove to be challenging due to this condition being an infrequent encounter.