Severe Cutaneous Adverse Drug Reactions: From Causes to Mechanisms

INTRODUCTION: In the context of adverse drug reactions (ADR), skin manifestations are among the most frequent and often of such severity as to require access to the emergency room for emergency injection therapy. In this article, we wanted to describe the characteristics of severe skin reactions both from a clinical point of view and with regard to the mechanisms and drugs most often involved in the cause. METHODS: Both the use of personal paper books and international website databases such as PubMed, Scopus, Google Scholar, and ResearchGate were used to develop the article, typing in keywords such as “skin ADR,” “severe drug reactions,” “Lyell or Steven-Johnson syndrome,” associated with specific compound names. We have focused on recent articles and only those related to severe ADRs. RESULTS AND CONCLUSIONS: With regard to cutaneous ADRs, mild or moderate presentations can be distinguished, such as morbilliform or scarlet eruptions with or without systemic symptoms, which are fortunately more frequent and generally treatable through the use of partially injected drugs and with oral therapy, and which self-resolve in a few days. Up to severe and potentially fatal erythrodermal forms such as DRESS or Stevens-Johnson and Lyell's syndromes, two different phases of the same process, with dermatological pictures similar to burns. Lists of higher-risk drugs have been established, and every physician, including general practitioners, should know their potential for toxicity before prescribing and the need for closer clinical monitoring. Pay attention to the differential diagnosis with infectious processes, sometimes concomitant, and to primary forms of dermatosis such as severe forms of psoriasis or acne.