This best selling book reviews that basic arithmetic required to calculate drug dosages accurately and quickly - an essential skill for every nurse. Example are drawn from clinical practice. Explanations and graded exercises (with answers) cover the calculations required to administer injections, tablets and mixtures, to dilute solutions, to arrive at different drip rates and to administer paediatric dosages safely. In this new edition all drug usage material has been reviewed and updated. New exercises have been added to added to assist in the learning process.