Most 503B compounding facilities, or compounding outsourcing facilities are challenged to prepare and submit regulatory responses to the US Food and Drug Administration (FDA). FDA inspections are considered as having stringent regulatory requirements and usually to be extremely different from a Board of Pharmacy inspection. During the presentation, a brief overview of the FDA inspection process will be reviewed. Explaining what a FDA 483 observation is, what are the FDA expectations for 483 observation responses, and what are the regulatory outcomes associated with FDA 483 observations. Examples of 503B 483 observations and 503B compounding outsourcing facility's responses will be reviewed and discussed.