Methods: This RCT included 60 patients (30 in control and 30 in intervention) between 18 and 80 years old, scheduled for elective single or double-level lumbar spine surgeries through the posterior approach. Intervention group (MBP) received PEGLEC, tablet Metronidazole 400 mg twice daily (BD), tablet Cefuroxime 500 mg BD, and probiotic (Bacillus clausii ) on pre-operation day, whereas the control (non-MBP) had no specific bowel preparation but received only a placebo. Outcome parameters included time to first flatus, bowel sound, and first defecation, which were compared between the two groups. Results: Demographic data such as age, sex, body mass index, level of surgery, and intraoperative data such as duration of surgery and blood loss were similar without significant differences. The time to first flatus, bowel sounds, and first defecation was not statistically significant, but POI was seen in 6.67% of patients, all belonging to the MBP group. No correlation observed between the duration of the ileus and the intraoperative blood loss and duration of surgery. Conclusions Bowel preparation may not be necessary for patients undergoing posterior lumbar spine surgery involving a maximum of two levels.