The aim of this study was to review all the published articles in the English language literature regarding the systemic effects of epidural corticosteroid injections (ESIs) in humans. ESIs are among the procedures that are most commonly used to manage chronic back pain. However, there has been no conclusive review on the systemic effects of this popular procedure. Reports were searched for in MEDLINE and EMBASE using the terms 'epidural' and 'steroids', 'corticosteroids' or 'glucocorticosteroids' up to and including the year 2012. Reports were also located by examining the references in the identified articles. We concluded that even if epidural steroid injection is one of the most widely- -used techniques to treat radicular pain, it must be administered cautiously, with careful monitoring for systemic side effects. At the very least, a standardised protocol is necessary.