What should not be included on the outside of a controlled substance mailing package?

The inclusion of indications of the package's contents on the outside of a controlled substance mailing package is prohibited due to security and legal concerns. Controlled substances are tightly regulated to prevent misuse, abuse, and illicit distribution. Clearly labeling a package with indications of its contents could potentially alert unintended recipients or criminals to the presence of drugs, increasing the risk of theft or illegal access.

In contrast, including the return sender's name is necessary for accountability and may be required by postal regulations. Standard postal information is necessary for the proper handling and delivery of mail, ensuring that it reaches the intended destination. Fragile stickers help ensure careful handling of items that are breakable, which is an important aspect of shipping. Therefore, while various pieces of information are required or beneficial for mailing packages, the explicit indication of contents pertaining specifically to controlled substances must be avoided to maintain safety and compliance with regulations.