To our knowledge, there is no high-quality evidence (ie, RCT data) on the use of IVIg in TEN. The data from the next best level of evidence (ie, the well-defined EuroSCAR7 cohort study) do not suggest a reduction in mortality from IVIg use, but suggest some possible evidence of harm, although the data are limited because they include SJS and SJS/TEN overlap. The remaining case series all suffer from a high risk of selection, performance, information, attrition, and publication bias, and are almost impossible to interpret. Few of the case series described comparator treatments. Some used historical controls, which are inappropriate given the advances in intensive supportive care in acute medicine that have occurred over the past 20 years. Furthermore, many control patients were treated concurrently with other active management (cyclosporine, cyclophosphamide, surgical debridement, and plasmaphoresis), making comparison impossible. Doses of IVIg varied across the studies, as did time of initiation. Similarly, the definition of TEN by TBSA affected with epidermal detachment varied across the studies reviewed, which also makes comparisons between studies challenging. Our stated definition was “epidermal detachment of over 30% of TBSA, ” but we have included studies in which there is some ambiguity regarding the TBSA involved and whether that involvement is all epidermal detachment or in some cases partly erythema. Not all studies recorded SCORTEN for all patients, thus not allowing assessment of severity to be made. Some patients had received intravenous corticosteroids prior to admission, and the specific outcome for these patients were not reported separately.