TREATMENT SELECTION AND PRESCRIBING

Rational Drug Selection

Define the Patient’s Problem

• Establish the working diagnosis and the degree of diagnostic certainty. A medication may obscure symptoms, delay the correct diagnosis, or create avoidable harm when the problem has not been adequately defined.
• Determine severity, urgency, expected course, and whether immediate treatment is needed before diagnostic evaluation is complete.
• Review previous treatment, allergies and reaction details, adverse drug reactions, current prescriptions, over-the-counter products, supplements, substance use, adherence, and access barriers.
• Identify pregnancy or lactation, age-related considerations, kidney and liver function, comorbidities, vital signs, relevant laboratory results, and potential interactions.

Specify the Therapeutic Objective

• State what treatment should accomplish. The objective may be cure, symptom relief, replacement of a deficiency, or long-term prevention (Woo & Robinson, 2019).
• Use a measurable target when possible. Define the expected magnitude and timing of response.
• Distinguish a surrogate outcome, such as a laboratory value, from the patient outcome the surrogate is intended to improve.
• Include the patient’s goals and acceptable tradeoffs. A technically effective regimen can fail when its burden, adverse effects, or cost conflicts with what the patient can sustain.

Compare Treatment Options

• Begin with current evidence-based guidelines and high-quality evidence that apply to the patient’s condition and population.
• Compare efficacy, absolute benefit, time to benefit, adverse effects, contraindications, interactions, therapeutic index, and monitoring requirements.
• Evaluate pharmacokinetics and pharmacodynamics in relation to route, onset, duration, organ function, age, pregnancy, genetic factors, and concurrent therapy.
• Consider nonpharmacologic treatment and watchful waiting when either may meet the objective with less risk.
• Use number needed to treat and number needed to harm when valid estimates are available and the study population and follow-up period resemble the clinical situation.

Individualize the Choice

The course mnemonic I Can PresCribE A Drug organizes the factors that should be reviewed before selecting a medication. The checklist below applies those factors to the individual patient (Woo & Robinson, 2019).

• Indication: The medication directly addresses the diagnosed or strongly suspected problem.
• Contraindications and precautions: Patient characteristics do not make the expected harm unacceptable.
• Efficacy: Evidence supports a clinically meaningful benefit for the intended outcome.
• Adverse effects: The expected adverse-effect profile is acceptable and manageable.
• Dose, route, interval, and duration: The regimen accounts for pharmacokinetics, organ function, formulation, disease severity, and treatment goal.
• Interactions: The medication list has been reviewed for pharmacokinetic and pharmacodynamic interactions, duplication, and cumulative burden.
• Adherence and feasibility: The patient can obtain, administer, store, and monitor the treatment.
• Cost and coverage: The expected out-of-pocket cost and formulary requirements do not make the regimen inaccessible.

Provider and System Influences

• A personal formulary can improve familiarity with commonly used medications, but it should remain limited, evidence based, and regularly updated rather than becoming a substitute for comparison (Woo & Robinson, 2019).
• Complex patients may require a systematic review beyond the usual personal formulary, including current guidelines, interaction resources, organ-function adjustments, and consultation when needed (Woo & Robinson, 2019).
• Payer formularies, prior authorization, and pharmacy availability can affect access. Coverage should be considered without allowing cost alone to displace clinically necessary treatment.
• Pharmaceutical promotion is a source of product information but is not an independent evidence review. Claims should be checked against primary evidence, guidelines, and unbiased drug information (Woo & Robinson, 2019).
• Guideline updates may change first-line therapy, monitoring, or treatment thresholds. Confirm that the recommendation is current and applicable to the patient’s population and setting.

Start Treatment Safely

• Write a complete, unambiguous prescription using the generic name when appropriate. Include strength, dosage form, route, dose, frequency, duration or quantity, refills, and indication when it improves safety.
• Reconcile what the patient should start, continue, change, hold, or stop.
• Avoid unnecessary therapeutic duplication and confirm whether a previous medication requires tapering or washout.
• Use the lowest effective starting dose when patient sensitivity, uncertainty, or a narrow therapeutic window warrants conservative titration.

Patient Education and Shared Decisions

• Explain the purpose of treatment and the expected time to benefit in plain language.
• Review how and when to take the medication, what to do after a missed dose, relevant food or substance interactions, storage, and any required technique.
• Separate common, manageable effects from serious findings that require urgent evaluation.
• Explain the monitoring plan and when the patient should expect follow-up, laboratory testing, or dose adjustment.
• Use teach-back to identify misunderstanding and document the decision when the patient declines or chooses among reasonable options.

Monitor Effectiveness and Safety

• Define the outcome measure, safety measure, follow-up interval, and person responsible for reviewing results before treatment begins.
• Passive monitoring relies on the patient to report response or problems. Active monitoring schedules assessment, laboratory testing, drug levels, or other measurements. Higher-risk therapy generally requires a more explicit active plan.
• At follow-up, assess benefit, adverse effects, adherence, access, interactions, and whether the diagnosis or therapeutic objective has changed.
• Continue, titrate, switch, deprescribe, or refer based on the balance of benefit and harm rather than continuing a medication indefinitely by default.

Common Prescribing Errors

• Treating a symptom without reconsidering the diagnosis when the expected response does not occur.
• Selecting a familiar medication without comparing contraindications, patient factors, monitoring burden, and current evidence.
• Starting therapy without defining when or how effectiveness will be judged.
• Labeling nonadherence as patient refusal without evaluating cost, regimen complexity, health literacy, adverse effects, competing priorities, and access.
• Adding medication to treat an adverse effect without first determining whether the original drug can be reduced, replaced, or stopped.

Related YourDNP Resources

• Pharmacokinetics
• Pharmacodynamics
• Pharmacoeconomics
• The APRN Prescriber Role
• Quiz: Foundations of Pharmacology

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References

Woo, T. M., & Robinson, M. V. (2019). Rational drug selection [PowerPoint slides]. F. A. Davis.