Completely revised and updated to include the latest practices and medication, the Ninth Edition maintains its user-friendly structure and offers students a comprehensive yet accessible drug calculation text and workbook. Using the dimensional analysis format, this invaluable resource begins with simple arithmetic and progresses to the most complex drug calculation problem, enabling students to develop the mathematical skills required for medical dosage calculations. With a host of pedagogical aids that includes case studies, self-tests, practice problem sets, and a new Companion Website. This text provides students with both the skills and understanding necessary to master this crucial area of nursing studies.