Drug calculations part 2: alternative strategies to the formula.

Drug calculations are an essential skill for nurses. The clinical skill of performing a drug calculation has come under recent scrutiny, resulting in the development of essential skills clusters in which pre-registration nurses must be competent before qualifying (Nursing and Midwifery Council 2007). The focus on drug calculation skills places renewed emphasis on how these skills are taught in higher education institutions and how they are learned by students theoretically and in clinical practice. Part 1 of this article (Wright 2008) examined the frequently cited drug formula as a method for calculating drug dosages, demonstrated the complex mathematical knowledge and skills required to use this method and the potential problems that reliance on this method could pose. Part 2 outlines other methods and strategies that can be used to calculate drug dosages, while keeping the calculation close to the clinical context.