For a study, the multiple drug hypersensitivity syndrome (MDH) was a separate clinical entity that differs from cross-reactivity and flare-up responses. Following its first presentation in 1989 by Sullivan et al., various writers had addressed the concerns that underlined the unusual kind of drug hypersensitivity. The issue was still debatable on whether the condition was a single entity or might be further subdivided into many entities. On MDH, there were few case reports, case series, or investigations involving very large populations. The phrase is used in a variety of contexts in the literature, with varying meanings. Given the recent advances in the study of drug hypersensitivities in general, as well as the ongoing research into severe cutaneous adverse reactions in particular, a careful examination of the subgroup of patients with an immunological basis for MDH enabled the generation of possible pathogenetic hypotheses for future studies. The developing findings, together with the studies (despite their limitations) that indicated the incidence of this illness in adult and pediatric patients, needed to be confirmed in bigger studies with well-defined populations.

Bringing together the expertise of organizations working in the field of drug allergy aided in the advancement of information about this unusual kind of drug hypersensitivity.