The NDC, or National Drug Code, is a unique 10-digit or 11-digit number, and a universal product identifier of medications.  The codes can be used to help identify the labeler (manufacturer, repackager, or distributor) of the medication, the specific strength, dosage form (i.e. capsule, tablet, liquid) and formulation of a drug, the package sizes and type of package.

NDC information is relevant to allergies for which the "Substance" a client is allergic to is a medication; however, not all medications have an NDC Code. Medications are assigned NDC codes based on the RxNorm identifier. Some RxNorm identifiers are not specific enough to have an NDC code which reflect particular packaging that a medication comes in, not just a compound, strength, and unit. To select a specific RxNorm code associated with NDC codes, after an RxNorm code is assigned during the data entry process, click the RxNav pop-out and select a record from "Branded Drug or Pack," and then copy the "RxCUI" into the RxNorm field.

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