Evaluating drug-related problems in narrow therapeutic index medications: The critical role of clinical pharmacists in patient safety

Background: Drug-related problems (DRPs) associated with narrow therapeutic index (NTI) drugs present significant challenges in clinical practice, often leading to adverse patient outcomes.
Objective: This study aimed to evaluate the incidence and types of DRPs linked to NTI drugs compared to non-NTI drugs and to assess the role of clinical pharmacists in mitigating these issues.
Methods: A total of 85 DRPs were identified, with common types including untreated indications (30.58%), unnecessary drug treatments (21.17%), and incorrect dosages (15.29%).
Results: A total of 273 prescriptions were analysed, of which 91 (33.33%) included at least one narrow therapeutic index (NTI) drug. Among these, the majority (86%) contained only one NTI drug. A total of 85 drug-related problems (DRPs) were identified, with 17.64% being associated with NTI drugs. The most common types of DRPs were untreated indications (30.58%) and unnecessary drug treatments (21.17%). Additionally, DRPs were more prevalent in non-NTI drugs (82.36%). The presence of multiple comorbidities was correlated with a higher incidence of DRPs. Patients with DRPs experienced longer hospital stays (average of 10 days), compared to those without DRPs (6 days). Statistical analysis revealed a significant difference in the incidence of DRPs between NTI and non-NTI drugs (p < 0.05).
Conclusion: This underscores the critical importance of clinical pharmacists in managing high-risk medications effectively. These findings highlight the need for structured pharmaceutical care and enhanced collaboration within healthcare teams to optimize medication management and patient safety. Future research should focus on standardized guidelines for managing NTI drugs and further exploring the economic implications of clinical pharmacy services in reducing DRPs.