Which of the following are primary considerations in drug therapy?

The primary consideration in drug therapy is the drug's action. Understanding the mechanism of action is crucial because it informs healthcare providers about how the drug works in the body, which helps in determining its effectiveness for treating a specific condition. This knowledge allows practitioners to make informed decisions regarding appropriate prescriptions, potential interactions with other medications, and side effects that may arise from the drug's action.

While indication codes, dosage forms, and drug packaging are also important elements in the overall context of drug therapy, they do not hold the same foundational role as understanding the drug's action. Indication codes provide information about what conditions a drug is approved to treat but do not give insight into how the drug functions biochemically. Dosage forms pertain to the physical form of the medication, such as tablets or injectables, and are important for administration but not as central to therapy as the action itself. Drug packaging relates to how the medication is presented and may affect compliance or safety but does not influence the therapeutic approach in the same way. Therefore, identifying the drug's action is central to effectively implementing drug therapy.