What essential information must be included in the directions for use on a prescription?

The correct choice emphasizes that directions for use on a prescription must be clear and detail both the dosage and frequency of administration. This clarity is crucial for ensuring patient safety and facilitating proper medication management. When patients receive clear instructions, they are more likely to adhere to their medication regimen, understand how and when to take their medication, and avoid potential medication errors.

Including dosage provides the specific amount of the medication the patient should take, which is vital for achieving the desired therapeutic effect. Specifying the frequency indicates how often the medication should be taken, which helps in maintaining effective drug levels in the body and prevents potential overdosing or underdosing.

The other options, while relevant to some extent, do not encompass the full requirements for prescription directions. Including only the dosage amounts does not adequately inform the patient about when to take the medication, which is crucial for proper adherence. Mentioning the drug name and potential side effects may be important information but does not encompass the specific instructions a patient needs to safely and effectively use the medication. Lastly, providing just the name of the prescriber is irrelevant to the directions for use and does not help the patient with how to take their medication correctly.