Spelling matters. Just Say No? Perhaps, Just Say KNOW! Substances will change controlled substances classes in the future, just as ethyl alcohol had in the past, but their respective pharmacology remain the same. Because of this, we, as healthcare professionals, need to provide impactful patient care with expanded knowledge of substances of abuse. In this program, we will review a multitude of substances of abuse, broken down into therapeutic classes and subclasses, with particular attention to structural nuances, clinical pearls, mechanisms of action, dosages, and interactions. This dynamic discussion will provide a broader depth of knowledge than the average clinician is ever armed with for patient care, while serving as the introduction for the much more comprehensive Substances of Abuse Specialty Pharmacist Certificate. Just Say NOW.