What is required on every prescription for a controlled substance?

The requirement for a physician's signature and a DEA number on every prescription for a controlled substance is mandated by regulations to ensure that the prescription is legitimate and authorized. The physician's signature verifies that a licensed medical professional has evaluated the patient and deemed that the medication is necessary, thus safeguarding against misuse or unauthorized dispensing of these drugs. The DEA number is essential as it identifies the healthcare provider as someone who is legally allowed to prescribe controlled substances, further reducing the risk of abuse and ensuring compliance with federal and state laws regarding the prescription of such medications.

In contrast, the other options do not meet the necessary legal requirements for prescribing controlled substances. While a date and patient signature might be important in other contexts, they do not specifically pertain to the legality of controlled substance prescriptions. A pharmacist's approval is not required for the prescription itself; rather, it is the pharmacist's responsibility to verify the prescription and ensure that it complies with all legal regulations before dispensing. A printed label is related to the packaging and dispensing process and does not constitute a requirement for writing the prescription itself.