Pharmacokinetic Principles of Dosing Adjustments: Undersing the Basics

American Journal of Pharmaceutical Education, Fall 2001 by Hodges, Brian M

RONALD D. SCHOENWALD. Pharmacokinetic Principles of Dosing Adjustments: Understanding the Basics. Lancaster PA: Technomic Publishing Company, Inc., 2001. xii 258 pp., 72 figs., 32 tbls., $69.95.

The subtitle, Understanding the Basics, accurately describes the author's approach in writing this introductory text. In the preface, he states that the goal of the text is "to provide the concepts used to formulate approaches but was not intended to be a clinical guide to dosing adjustments." This text serves as an introduction for the student, or a re-introduction for the practicing pharmacist, to the basic pharmacokinetic concepts that form the foundation for calculating pharmacokinetic dose adjustments.

The book is divided into four sections: Basic Concepts, Parenteral Dosing Adjustments, Oral Dosing, and Advanced Considerations, Each section is further divided into a total of ten chapters. The Basic Concepts section contains chapters on Pharmacokinetic Processes, Kinetic Processes Applied to the Whole Body, Disposition Parameters, and Parameters Used in Adjusting Doses. The lone chapter in the Parenteral Dosing Adjustments section is entitled Infusion. Chapters in the Oral Dosing section include Important Parameters, Bioavailability/Bioequivalence, and Multiple Dosing Regimens. Finally, the Advanced Considerations section introduces readers to the Two-Compartment Model and Non-Linear Pharmacokinetics.

Each chapter begins with a set of study guide questions. These questions are clear, well written, and help readers focus on the most important concepts presented. At the end of each chapter is a set of study problems. The problems allow readers to apply the concepts presented, and with the answers found in the appendix, serve as a means of self-assessment.

With the focus of the book in mind, concepts are presented in a simple but scientifically sound manner. Equations are presented in their most universal form, and are not altered to perform dosing calculations for specific drugs or drug classes. Rather than introducing equations through extensive mathematical derivations, Schoenwald employs more intuitive and physiologic explanations. The examples illustrating pharmacokinetic concepts are easily understood, even for readers whose calculus classes are but a distant memory. This seems to be especially true of the chapters in the Basic Concepts section. Figures and tables are used efficiently, and they are labeled in a way that quickly acclimates readers.

This book's strength is also its weakness. While it provides an easy to understand introduction to the concepts and skills needed to calculate dose adjustments for patients, it does not go beyond that. Those looking for a text covering the latest techniques in pharmacokinetics research or to provide in-depth instruction on dose optimization of clinically monitored drugs should probably look elsewhere. Therefore, it would probably not be appropriate as the lone text used in advanced clinical pharmacokinetics courses or graduate level pharmacokinetics courses.

Practicing pharmacists needing to recall basic pharmacokinetic concepts will find this to be a helpful reference, but there are a number of clinical pharmacokinetics references available that provide more of the information needed to calculate specific pharmacokinetic dose adjustments. With its concise presentation and user-friendly examples, this text would best be utilized in introductory pharmacokinetics courses at the undergraduate level. It would also be a valuable addition to the reference collection of any medical library or drug information center.

Brian M Hodges

West Virginia University