Life of a Pill: An Introductory Active Learning Exercise for First Year PharmD Students

Abstract

What happens to a pill when it is swallowed? How does the body react to the foreign drug molecules inside the pill? What is the fate of the drug molecules? These are questions that beginning pharmacy students typically have, but in the sea of the introductory topics that must be mastered, they seldom have the time to really appreciate the journey a drug takes though the body and the processes that define the journey. A drug’s chemical structure determines its physicochemical properties. These properties, in concert with the pharmacokinetic processes of absorption, distribution, metabolism and excretion (ADME), dictate the fate of the drug. In order to tell this story, we have devised an active learning exercise, called “Life of a Pill” (LOAP).LOAP Exercise is offered in the introductory course of pharmaceutical sciences to the first year PharmD students in their very first semester. The objective of this exercise is to help the students understand how the ADME of any drug molecule closely depends on its various physicochemical properties such as ionization (pKa), lipophilicity (LogP/LogD), chemical bonding etc. In this small group exercise, each group is assigned a drug to analyze through a set of questions. The groups research their drug based on these questions, and write a detailed report on their discussion and findings. These reports are graded using a rubric that assesses knowledge, analysis, and writing and organization skills. Prior to the exercise, the students take a 5 question multiple choice quiz on topics related to lipophilicity, drug ionization and drug metabolizing enzymes. Upon completion of the exercise, the students are tested again on those same topics in their summative examination with similar types of questions.While grading the LOAP reports, we found that the students were able to adequately explain the ADME properties of their assigned drug on the basis of lipophilicity, chemical structure and ionization. They were able to appreciate how the drug’s pKa/pKb values affected absorption through the GI tract; they were able to look at the LogP and the LogD values of the drug and predict bioavailability as well as the ability to cross the blood brain barrier. In addition, by comparing the LogP values of the metabolites to the parent drug, they were able to explain how metabolism typically makes the drug less lipophilic facilitating its elimination through kidney. Finally, the students examined any drug‐drug interactions, and were able to explain either the pharmacokinetic or the pharmacodynamic nature of those interactions. Additionally, the student average score increased from 52% (n=80) in the quiz given prior to the LOAP exercise to 84.25% (n=80) in their summative exam that was given upon completion of the LOAP exercise.LOAP exercise has been developed and implemented as an active learning exercise to introduce the concepts of ADME of drugs on the basis of the drug’s physicochemical properties to the first year PharmD students. It is an application‐based group exercise that helps students understand important foundational concepts in both physicochemical properties and pharmacokinetics, and provides students with a mental picture of how these concepts relate to the journey of a drug through the body.Support or Funding InformationThis study is supported by Touro University CA‐College of Pharmacy.