OBJECTIVES:  To examine resource utilization associated with the use of Rasagiline or Selegiline, two commonly prescribed MAOB inhibitors for the treatment of Parkinson's Disease (PD).  METHODS: Data for this retrospective study were obtained from the US i3 LabRx database over the time period from January 1, 2006 through December 30, 2010.  Patients were included in the analysis if they were prescribed Rasagiline or Selegiline (with first such date identified as the index date), were diagnosed with PD (ICD-9 code 332.0), and had continuous insurance coverage from 6 months prior through 12 months post index date.  Analyses are primarily descriptive in nature, with differences in categorical variables analyzed using chi-square statistics and differences in continuous variables analyzed using t-statistics.  RESULTS: There were 1242 individuals included in the study - 926 initiated on Rasagiline and 316 initiated on Selegiline.  Patients initiated on Rasagiline, compared to those intitiated on Selegiline, were significantly younger (63.2 years vs. 65.4 years; P=0.0020).  Patients initiated on Rasagiline were significantly less likely to be diagnosed with chest pain (16.41% vs. 21.52%; P=0.0402) or headaches (4.97% vs. 9.49%; P=0.0037).  Patients who intitated on Rasagiline were significantly more likely to visit a neurologist (93.63% vs. 89.24%; P=0.0105).  Compared with Selegiline use, initiation on Rasagiline was associated with significantly fewer inpatient visits (1.58 vs. 2.94; P=0.0236) and significantly shorter hospital length of stay (4.71 days vs. 8.78 days; P=0.0216).  CONCLUSIONS: Results from this retrospective study indicate that, patients who initiated therapy with Selegiline, compared to Rasagiline were more likely to experience side effects of chest pain or headaches.  In addition, these patients were more likely to have a greater resource utilization due to the number and significantly longer lengths of hospitalizations.