Acute kidney injury and 'nephrotoxins': mind your language

The introduction of the term 'acute kidney injury' (AKI) along with an international classification scheme,¹ caused some initial confusion, but most clinicians and many patients now understand that the term 'injury' denotes damage to the internal workings of the kidney, rather than physical trauma. However, of greater concern is the use of the term 'nephrotoxic' to include drugs that are, in most settings, nephroprotective. We argue that this imprecise terminology, unfortunately adopted by the National Institute for Health and Care Excellence (NICE) among others, is potentially harmful, and that the terms 'nephrotoxin' and 'nephrotoxic' should not be used to describe haemodynamically mediated and fully reversible effects of some drugs on excretory function.