Although allergies to antibiotics are commonly stated, allergies to cephalosporin antibiotics are uncommonly reported. Furthermore, dermatologic and systemic reactions from cephalosporin exposure involving end-organ damage are rare. We present a case of cephalexin, a cephalosporin, induced hypersensitivity vasculitis causing characteristic non-blanching purpuric lesions along with acute kidney failure necessitating hospitalization, corticosteroids, and initiation of hemodialysis.