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Companies Recycle Their NDC Numbers

Donna Young

Five years after the last commercial shipment of a discontinued drug product, its national drug code (NDC)—the unique 10-digit, three-segment number that identifies the manufacturer, products and package size—can be reassigned to another drug product, according to a long-time FDA regulation.

Recent notices from information-system management companies that they would be "deleting, readding, and reusing" NDC numbers and that pharmacy databases need to be updated prompted some pharmacists to contact ASHP. The pharmacists were concerned that the recycling effort could ultimately lead to drug errors.

But Kathy Smith, drug registration and listing database project officer for FDA’s Division of Data Management and Service, said she is unaware of any reported adverse drug events related to the redistribution of NDC numbers.

"It’s highly unlikely, given that the numbers are broken down into three segments, and potentially, it would take a long time before a number is used again," she said.

Who Assigns the NDC Digits?

FDA assigns the first segment of national drug code (NDC) digits, known as the labeler code. A labeler is any firm that manufactures, repackages, or distributes a drug product.

The second segment, assigned by the labeler and known as the product code, identifies the specific strength, dosage form, and formulation.

The package code, the third segment of digits, identifies the package size. Like the second segment, the third segment is assigned by the labeler.

According to FDA, NDC numbers must be assigned in one of the following configurations: four digits, four digits, two digits; five digits, three digits, two digits; or five digits, four digits, one digit.

Once a drug company has selected a configuration, it must stay with the same one, Smith said.

Some drug companies that have several divisions have more than one labeler code assigned, Smith said. She is aware of one company that has 12 labeler codes assigned by FDA.

The NDC system was originally developed as part of a Medicare outpatient-drug reimbursement program, according to FDA.