Endocrine therapies and QTc prolongation.

QT interval represents the period between the initiation of depolarization and the end of repolarization of the ventricular myocardium. Excessive prolongation of this interval may drive to a potentially fatal ventricular tachyarrhythmia known as "torsades de pointes". Agents used to manage many endocrine disorders have been linked with QTc alterations. Among them, oral antidiabetic agents, lipid lowering and anti-obesity drugs, somatostatin analogues, thyroid and anti-thyroid agents, and adrenal steroids should be considered. Nevertheless, it is very well known that some endocrine diseases are associated with constraints in the repolarization reserve, and, as a consequence, with QTc prolongation. Besides, some disturbances in the clearance of certain drugs are more frequent in patients affected by selected endocrine entities. Taking these into account, the purpose of this article is to review the behavior of the most widely used drugs in endocrinology with regards to their potential QTc prolongation effect in human beings.