what do ndc numbers represent
National Drug Code Description. The NDC is a number that identifies a specific drug. The NDC number consists of 11 digits in a 5-4-2 format. NDCs printed on packages often have fewer than 11 digits, with hyphens (-) separating the number into three segments. A complete 11-digit number must have five digits in the first segment, four digits in the second segment, and two digits in the last segment.