What it means
The FDA describes the NDC as a 10-digit, three-part number. The first part identifies the labeler, the company that makes or distributes the drug. The second identifies the product, including strength and dosage form. The third identifies the package size and type. You will see it printed on the carton, often with dashes.
Different strengths of the same medicine, such as each pen dose, have different NDCs. So do different package sizes. That is why a pharmacy or insurer may ask for the exact NDC when checking coverage or price.
Billing systems often use an 11-digit version with a padding zero. The FDA has also finalized a move to a uniform 12-digit format that takes effect in 2033.
The FDA's public NDC Directory lets you look up a product by name or number. Compounded products made by pharmacies usually do not have the NDC of an approved brand product.
Why it matters
Matching the NDC confirms you are getting the exact approved product and dose your prescription and coverage name.