What letter position in the DEA number must correspond to the prescriber's last name?

The correct answer is the second letter of the DEA number, which corresponds to the prescriber's last name. The structure of a DEA number consists of two letters followed by seven digits. The first letter identifies the type of registrant, which can include practitioners, hospitals, or pharmacies. The second letter is specifically derived from the prescriber's last name.

For instance, if a prescriber's last name is "Johnson," the second letter of their DEA number would be "J." This coding system allows for easy identification of the prescriber associated with the DEA number and helps prevent misuse and confusion in prescription processing.

Understanding this structure is important for verifying the legitimacy of a DEA number and ensuring compliance with regulations.