- The initial step in the process of rational prescribing is defining the patient's problem.
- This step is crucial because it involves accurately diagnosing the patient's condition, which forms the foundation for all subsequent decisions in the prescribing process.
- Without a clear and precise understanding of the clinical problem, it is impossible to choose the appropriate drug, monitor therapy effectively, or anticipate potential drug interactions.

- Once the patient's problem is clearly defined, the next step is to select the most suitable drug that addresses the specific condition.
- After initiating therapy, it is essential to monitor the therapeutic response to ensure the drug's effectiveness and safety.
- Finally, evaluating potential drug interactions is important to minimize adverse effects and optimize the patient's treatment regimen.

In summary, accurate diagnosis and problem definition are the key initial steps that guide rational prescribing and improve patient outcomes.

Reference: Goodman & Gilman's The Pharmacological Basis of Therapeutics, 13th Edition, Chapter 2: Principles of Pharmacology/ Page 20