Background <p>A team-based approach is essential to provide cancer patients with high-quality treatment. To ensure the best possible care while reducing the workload of physicians, Ehime University Hospital has introduced three protocol-based pharmacotherapy management (PBPM) strategies in the field of chemotherapy. First, we introduced PBPM to avoid reactivation of hepatitis B virus (HBV) in patients receiving immunosuppressive therapy or chemotherapy. In this PBPM strategy, pharmacists added laboratory test orders for patients who require regular HBV-DNA quantification (HBV-PBPM). Second, we devised PBPM for measurement of the urine protein/creatinine ratio (UPC) in patients receiving anti-vascular endothelial growth factor therapy. Finally, we introduced PBPM for measurement of serum magnesium in patients receiving anti-epidermal growth factor receptor antibody therapy (Mg-PBPM). In this study, we evaluated the usefulness of these three PBPM strategies in outpatients receiving chemotherapy.</p> Methods <p>The study included patients treated in the outpatient chemotherapy unit between July 2021 and February 2023. Rates of compliance with laboratory tests in the 6 months before and after introduction of PBPM were compared.</p> Results <p>Compliance with HBV-DNA quantification improved significantly from 66.3% before PBPM to 86.7% after implementation of PBPM (<i>p</i> = 0.002). The median duration of noncompliance was significantly shorter after initiation of PBPM (<i>p</i> = 0.021). Compliance with measurement of UPC was already greater than 95% before PBPM and showed no change after implementation (98.7% pre-PBPM vs 99.3% post-PBPM). Compliance with measurement of serum magnesium improved from 95.8% pre-PBPM to 99.2% after starting PBPM, but the improvement was not statistically significant.</p> Conclusions <p>Introduction of PBPM improves compliance with the laboratory tests required in cancer patients during chemotherapy and enables safer delivery of treatment.</p>