What must a label contain in addition to the manufacturer's name and address?

The requirement for a label to include an imprinted symbol, number, or letter serves a critical purpose in the context of ensuring safety and identification in pharmaceutical products. Such markings often give essential information about the drug, such as its specific formulation, strength, or the type of medication it is. This is especially important in preventing medication errors and aiding in the proper identification of products by both healthcare professionals and patients.

In many regulatory contexts, including those governed by the FDA or state pharmacy boards, unique identifiers help distinguish between different medications or different doses of the same medication, reducing the risk of confusion or mix-up, and contributing to better patient safety.

Other label components might be significant for various reasons, such as ensuring correct usage or storage, but the inclusion of an imprinted symbol or number serves more directly to uniquely identify the product in a way that enhances safety and compliance with regulatory standards.