Ever since attention was brought to the subject of medication errors by seminal works such as ‘To Err is Human’1 and ‘An Organisation with a Memory’,2 there have been continuing efforts to reduce preventable harms related to the prescribing, dispensing and administration of medicines. The focus on drug safety has resulted in new systems and processes such as ‘medicines optimisation’ that include regular medication reviews; the use of pharmacogenetic markers to predict harmful adverse drug effects; computerised prescribing support; and enhanced vigilance and error reporting systems. However, what can we learn from recent evidence highlighting that preventable errors persist in modern practice?

A study commissioned by the General Medical Council in 2009 reported a total mean prescribing error rate of …