Multiple drug hypersensitivity associated with severe cutaneous adverse reaction

Background Multiple Drug Hypersensitivity (MDH) was first described by Sullivan et al in 1989 as drug allergies to two or more chemically different drugs proven by in-vivo or in-vitro testing. Pichler et al added to this description by suggesting that there are two subtypes of MDH: one where sensitisation to different drug classes may occur simultaneously; the other, sequentially sometimes even years apart.