Although both mechanisms allow patients to access treatments or diagnostic modalities that might not otherwise be available outside of a clinical trial, there are differences in the origin (FDA versus patient and prescriber), tempo (immediate versus (usually) one month delay), and common setting (declared public health emergency versus (usually) smaller scale immediately life-threatening or serious disease or condition) between an EUA and EA, respectively. EUAs also differ from Expanded Access (also known as “compassionate use”) in that the latter are initiated for existing or submitted investigational new drug applications (INDs) by prescribers for individual patients or widespread use in order to gain access to an investigational medical product outside of clinical trials because there is no satisfactory alternative option available. Prescribers are still required to report serious adverse events from medication use under an EUA through the FDA’s MedWatch Program. The FDA provides recommended guidance to manufacturers and laboratories to conduct validation for proposed tests; consumers and health professionals are encouraged to report concerns about problematic devices or fraudulent practices. Please see the FDA’s Emergency Use Authorization page and FDA’s Expanded Access page for more information.