Mycophenolic acid (MPA) is an immunosuppressive antimetabolite used to prevent acute organ rejection and as a part of maintenance therapy in transplant patients. With the increasing application of MPA in solid organ transplantation, the necessity for more accurate drug dosing has become evident. Due to significant inter- and intra-individual pharmacokinetic variability and potential interactions with other drugs, monitoring plasma drug concentrations is crucial. For the implementation of therapeutic drug monitoring (TDM) of MPA, the area under the curve (AUC) is considered as a gold standard, aimed at optimizing personalized immunosuppressive therapy. The objective of this study was to evaluate the AUC and trough concentrations of MPA and analyse them according to defined therapeutic ranges and by gender. Additionally, compare the results obtained using different equations for calculation the AUC of MPA. Statistical analysis demonstrated no statistically significant differences between AUC values from the medical history and those obtained using Formula 1 (P = 0,6171). However, a comparison of the AUC with Formula 2 revealed a statistically significant difference between the obtained values (P = 0,0275). The reference interval for the AUC of MPA is 30 – 60 mg*h/L and only 50 % of patients have achieved the desired values. Analysis of trough concentrations of MPA revealed a statistically significant difference between genders (P < 0,0001). Furthermore, the analysis determined that 40.69 % of patients achieve values within the therapeutic interval of 1.9 – 4.0 mg/L, considering that all patients were receiving both MPA and tacrolimus. This thesis confirms the significance of a personalized approach to immunosuppressive therapy in post-transplant patients, underscoring the importance of therapeutic drug monitoring in optimizing clinical outcomes.