When evaluating the opioid crisis, research reveals that external factors—such as the volume of pre-filled syringes, or a default number of opioid tablets that could easily be ordered at discharge for the patient—can shift prescribing and compel emergency department (ED) physicians to administer or prescribe greater quantities of opioids. A new study published in the Journal of Medical Toxicology reveals that opioid prescribing behavior can also be decreased by external factors, such as a supply shortage.