Which piece of information is NOT required on a prescription label?

The correct choice indicates that a patient's physical appearance is not a required piece of information on a prescription label. Prescription labels are designed to convey essential information that is necessary for the safe and effective use of the medication.

Required elements on a prescription label typically include the prescribing practitioner's name, the patient's name, directions for use, and the name of the drug. These details ensure that the patient receives the correct medication, understands how to take it, and knows who authorized the prescription.

While a patient's physical appearance might be relevant in certain contexts, such as in healthcare settings where identification verification might be necessary, it does not contribute to the essential instructions and safety warnings that a prescription label provides. Thus, it is not mandated as part of the labeling requirements, making it the correct answer to this question.