Background: Transitions of care (TOC) and medication management for complex patients are high-risk periods prone to information loss and adverse drug events (ADEs). Multidisciplinary interventions, particularly those involving pharmacists, are increasingly utilized to bridge these gaps. This review evaluates the effectiveness of professional-led interventions, including antimicrobial stewardship (AMS), medication reconciliation, and specialized clinical protocols, on patient safety and clinical outcomes. Methods: Following PRISMA guidelines, we searched electronic databases (PubMed, Google Scholar, DOAJ) for studies published between 2012 and 2025. Data were extracted from 15 studies focusing on hospital-based and long-term care interventions. Results: Pharmacist-led AMS programs significantly reduced antibiotic use density by 22.28% in tertiary settings and up to 40% in ICUs. Transition of care services and community reconciliation effectively identified medication discrepancies and reduced ADEs. In emergency settings, pharmacist intervention corrected medication history errors in 93.1% of cases. Specialized protocols showed mixed results: perioperative oral care reduced postoperative pneumonia, whereas chlorhexidine was ineffective for ventilator-associated pneumonia. Closed-loop smartphone communication and manual call centers improved the accuracy of critical laboratory notifications over automated systems. Conclusion: Multidisciplinary, pharmacist-supported interventions are essential for reducing medication errors and optimizing drug therapy. Success is dependent on standardized, evidence based protocols and robust communication frameworks across the healthcare continuum.