Drug Utilization Review (DUR) and Drug Use Evaluation (DUE) Comprehensive Guide

Core Concepts of Drug Utilization Review (DUR) and Drug Use Evaluation (DUE)

• Definition of DUR: An authorized, structured, and ongoing review of prescribing, dispensing, and medication use. This process occurs at various stages, specifically before, during, or after therapy.

• Definition of DUE / MUE: Systematic, criteria-based evaluation of a drug or medication-use process. The primary goals are the optimization of outcomes, safety, and cost-effectiveness. In many clinical settings, Medication Use Evaluation (MUE) is the preferred contemporary term for this process.

• The Core Differentiating Idea:

  • DUR: Traditionally used to detect individual or population-level drug therapy problems. It acts as a diagnostic tool for medication management.

  • DUE: Functions to "close the loop." This involves taking direct action based on findings, providing feedback to clinicians, and conducting re-measurement to ensure improvement.

• Clinical Pharmacy Framework Objectives: The framework aims to be a concise method for preventing medication-related problems and converting review findings into measurable, quantitative improvements.

• The Teaching Hook/Heuristic:

  • "A DUR stops an unsafe order today."

  • "A DUE changes the system so the same unsafe pattern becomes less likely tomorrow."

• The Seven "Rights" of Medication Use:

  • Right patient

  • Right indication

  • Right drug

  • Right dose

  • Right duration

  • Right monitoring

  • Right cost

• Primary Pillars of Clinical Impact:

  • Quality of care

  • Patient safety

  • Therapeutic outcomes

  • Rational cost

DUR Classification and Timing

• Timing as a Timeline: DUR is classified based on three distinct moments relative to the administration of therapy: before, during, and after.

• 1. Prospective DUR (Before Therapy):

  • Timing: Conducted before the medication reaches the patient.

  • Goal: To prevent an error or a poor clinical choice before any potential harm can occur.

  • Clinical Examples: Checking for allergies, contraindications, therapeutic duplications, drug-drug interactions, and verifying the appropriateness of the dose and duration.

  • Real-world Practice Example: A pharmacist receiving a system alert regarding a potential interaction between warfarin and an NSAID before dispensing.

• 2. Concurrent DUR (During Therapy):

  • Timing: Performed during active therapy.

  • Goal: To adjust therapy in real-time based on the patient's clinical response, laboratory values, and overall status.

  • Clinical Examples: Adjusting doses for renal function changes, monitoring for toxicity, Therapeutic Drug Monitoring (TDM), facilitating IV-to-oral switches, and reviewing culture results to narrow therapy.

  • Real-world Practice Example: Monitoring a patient on piperacillin/tazobactam and adjusting the dose based on daily renal function changes.

• 3. Retrospective DUR (After Therapy):

  • Timing: Performed after medication use has already occurred.

  • Goal: To identify broad patterns of use and improve future prescribing habits.

  • Clinical Examples: Identifying patterns of overutilization or underutilization, excessive treatment durations, non-compliance with clinical guidelines, and overall cost trends.

  • Real-world Practice Example: A monthly review of asthma patients to identify those who are not receiving recommended controller therapy despite frequent rescue inhaler use.

Clinical Triggers and Explicit Criteria

• The Necessity of Criteria: Effective reviews require explicit, guideline-based standards applied to prescriptions, patient charts, dispensing records, or institutional audits.

• Key High-Yield Medication-Use Problems:

  • Indication: Identifying unnecessary drug use or therapy that is missing despite being indicated.

  • Effectiveness: Identifying the use of the wrong drug or a poor target response to the chosen drug.

  • Dose: Addressing doses that are too high, too low, or necessitate renal/hepatic adjustment.

  • Duration: Flagging excessive or otherwise inappropriate courses of therapy.

  • Safety: Checking for allergies, contraindications, and general Adverse Drug Reaction (ADR) risks.

  • Interactions: Screening for drug-drug interactions, drug-disease interactions, and duplicate therapy.

  • Monitoring: Checking for missing laboratory tests, TDM requirements, and follow-up parameters.

  • Use Pattern: Detecting overuse, underuse, misuse, or active abuse.

  • Cost/Value: Evaluating therapeutic alternatives and overall formulary fit.

• Prioritization for DUE Topics: Topics should be prioritized when the medication or process meets the following descriptors:

  • High-risk (narrow therapeutic index or high potential for harm).

  • High-cost (significant budgetary impact).

  • High-volume (used by a large portion of the patient population).

  • Problem-prone (historically associated with errors or difficulties).

  • Safety-linked (connected to a recent adverse event or safety signal).

Practical Workflow for Running a DUE/MUE

• Step 1: Selection: Select a target that is high-risk, high-cost, high-volume, or linked to a safety signal.

• Step 2: Define Criteria: Establish standards based on clinical guidelines and set a performance threshold (e.g., $90\%$ or $100\%$ compliance).

• Step 3: Data Collection: Determine the sample size, the review period, specific variables to be measured, and the data source.

• Step 4: Comparison: Compare actual compliance against the pre-defined criteria and thresholds.

• Step 5: Intervention: Implement changes such as clinical feedback, creation of order sets, provider education, or medication restrictions.

• Step 6: Re-measurement: Document the outcomes of the intervention and ensure the change is sustained over time.

Classroom Activity: 10-Minute DUR/DUE Drill

• Case Scenario:

  • Patient: 78-year-old with pneumonia.

  • Medication: Receives piperacillin/tazobactam.

  • Clinical Change: eGFR (Estimated Glomerular Filtration Rate) falls from $58\,mL/min/1.73m^2$ to $28\,mL/min/1.73m^2$ on the third day of therapy.

  • Microbiology: Culture results show susceptible E. coli.

  • Outcome: Therapy continues for a total of 8 days.

• Student Task:

  1. Classify the review timing.

  2. Identify medication-use problems.

  3. Propose a pharmacist intervention.

  4. Write one measurable DUE criterion.

• Expected Answer Pattern:

  • Timing: This is a Concurrent review (now, during therapy) and can be a Retrospective review (later, for pattern analysis).

  • Identified Problems: Failure to review renal dose, lack of de-escalation (switching from broad-spectrum to narrow-spectrum based on culture), inappropriate duration, and failure to adjust based on culture-directed therapy or monitoring.

  • Intervention: Pharmacist should intervene to adjust the dose for the new eGFR or recommend de-escalation to a narrower-spectrum antibiotic based on the E. coli susceptibility.

  • DUE Criterion: "$100\%$ of patients on Piperacillin/Tazobactam must have renal function reviewed within $48$ hours and the dose must be adjusted when eGFR < $40\,mL/min/1.73m^2$."

• Final Clinical Takeaway: DUR finds the problem. DUE/MUE proves whether the system actually changed to prevent it.