Background: Electrolyte disturbances are frequently encountered in patients with Type 2 Diabetes Mellitus (T2DM) and are closely associated with poor glycaemic regulation, renal dysfunction, cardiovascular complications, and increased morbidity. Pharmacist-led interventions have emerged as a valuable strategy for optimizing therapeutic outcomes; however, their influence on long-term electrolyte homeostasis remains inadequately characterized. Objective: To evaluate the longitudinal impact of pharmacist-provided educational and therapeutic interventions on electrolyte balance among patients with T2DM over a 12-month follow-up period. Methods: A controlled longitudinal study was conducted involving patients with T2DM allocated to either an interventional group receiving structured pharmacist-led care or a control group receiving standard management. Serial assessments of serum sodium, potassium, chloride, calcium, magnesium, and phosphorus were performed at baseline and at 3-, 6-, 9-, and 12-month intervals. Temporal changes in electrolyte parameters were analyzed using comparative statistical methods, with significance established at p<0.05. Results: Participants receiving pharmacist intervention demonstrated substantial and sustained improvements in electrolyte regulation throughout the study period. Significant reductions in serum sodium and potassium concentrations were observed in the interventional cohort, accompanied by progressive normalization of chloride levels (p<0.001). Magnesium concentrations increased markedly from baseline, indicating enhanced metabolic and cellular electrolyte equilibrium. Calcium levels remained physiologically stable, whereas phosphorus concentrations exhibited a modest but significant decline over time. In contrast, the control group displayed comparatively limited or inconsistent electrolyte modulation across follow-up assessments. The magnitude and consistency of change were significantly greater among intervention recipients, suggesting superior maintenance of electrolyte homeostasis. Conclusion: Pharmacist-led interventions exerted a pronounced positive effect on long-term electrolyte stability in patients with T2DM. Integrating clinical pharmacists into multidisciplinary diabetes care may facilitate improved metabolic regulation, enhance biochemical monitoring, and mitigate the risk of electrolyte-related complications, ultimately contributing to better clinical outcomes and disease management.