Which of the following segments in the NDC may contain characters other than digits in exceptional cases?

The package code segment of the National Drug Code (NDC) may contain characters other than digits in exceptional cases, making it the correct answer. The NDC is a unique identifier for medications and is composed of three segments: the labeler code, product code, and package code.

Typically, the labeler code is assigned to a specific manufacturer or distributor, and the product code identifies the specific drug formulation, strength, and dosage form. Both of these segments are strictly numeric and do not include characters outside of digits.

On the other hand, the package code is used to differentiate between different packaging sizes and types of the same product, and in exceptional cases, it can include characters or letters to denote specific packaging attributes. This flexibility in the package code segment allows manufacturers to convey more complex packaging information, which might not be strictly captured by digits alone.

Understanding this distinction is important when interpreting the NDC and identifying products in the context of pharmacy practice and regulatory compliance in Hawaii and beyond.