Most professionals will be familiar with, and consider, a drug’s effects when deciding treatment options but may not consider how that medication reaches its therapeutic target or how it is removed from the body afterwards. This is a potential oversight. Without a drug being available at a cellular level it cannot exert a therapeutic effect, and as the body naturally removes all foreign compounds, including drugs, the speed of elimination will reduce any therapeutic effect. An understanding of the processes by which the body handles drugs is essential to an understanding of the routes of administration, dosing regimens and the impact of chronic disease states on pharmacokinetics.