The impact of thalidomide use in birth defects in Brazil.

Although the thalidomide tragedy occurred more than 50 years ago, the medication is still being used worldwide for different reasons, and several aspects regarding its teratogenicity remain unsolved. Despite the strict regulation implemented, new cases of thalidomide embryopathy (TE) are still being registered in Brazil. Furthermore, the molecular processes that lead to malformations when the embryo is exposed to thalidomide have not yet been fully identified. In this article, we perform a critical analysis of thalidomide's history in Brazil, highlighting aspects of the occurrence of TE over the decades. Finally, we present the main perspectives and challenges for ongoing surveillance and prevention of TE in Brazil. The effective control of dispensing thalidomide, especially in areas where leprosy is endemic, is one of the most important and challenging points. Furthermore, the emergence of thalidomide analogues is fast approaching, and their availability would pose additional concerns. The understanding of the molecular mechanisms and targets of thalidomide in both experimental and human models is essential for generating new insights into teratogenic mechanisms, so that safer thalidomide analogues can be developed.