The equilibrium potential of an ion species is a crucial concept for medical students, as it is a prerequisite to fully understanding the pathophysiology of K+ imbalances (hyperkalemia and hypokalemia) in clinical practice. However, it remains a challenging concept because current medical physiology textbooks are too simplistic and overlook several essential points. In this article, we present a total of five small but impactful additions to advance the introduction of the equilibrium potential that will eliminate confusion and facilitate mastery-level comprehension.