Importance of a thorough drug history in presurgical patients.

A 72-year-old woman was admitted for a routine elective total knee replacement. By day 1 postoperative, she became hyponatraemic following an Addisonian crisis, leading to an admission into the intensive therapy unit (ITU). It was later during this stay in the ITU and on a retrospective drug history review that she was found to have taken clobetasol, a high strength topical steroid cream over the past 2 years. The authors alert the reader to the importance of specially asking patients about their use of current or recent topical steroid creams as they may not always volunteer this information. Sudden withdrawal of steroid supplementation in these patients in the preoperative period may result in catastrophic consequences.