A Disseminated Adverse Drug Reaction in a Child in Response to Beta‐Lactam Patch Testing

Patch testing is considered safe in the evaluation of selected non‐immediate drug hypersensitivity reactions in both children and adults. This report describes a 2‐year‐7‐month‐old boy whose index reaction to amoxicillin–clavulanate was a non‐severe but widespread maculopapular eruption that intensified with continued dosing. Because of its extent and progression, patch testing was performed before the planned drug provocation test. A disseminated maculopapular eruption developed after patch testing, with a strong positive (2+) reaction at 48 h. This case highlights that generalized cutaneous reactions may rarely occur after patch testing, even when the initial reaction is non‐severe.