Objective: Gastrointestinal dysmotility and constipation are common problems in hospitalized patients, especially the critically ill patients. Addressing and preventing the opioid inducing constipation adverse effects is essential to patient care. In this study we aim to assess the daily Fructo-Oligosaccharides (FOSs) proactively supplementation effectiveness on opioid induced constipation and its related complications. Materials and Methods: This retrospective study was conducted on 188 Eligible patients between Jan 2018 and May 2021, which were grouped to 2 comparative cohorts; patients who were on daily FOS proactively supplementation (Cohort I) and patients who were on our institutional protocolized bowel care management (Cohort II). An Independent and One Sample T-Tests were used to analyze all non-dichotomous comparative variables and for dichotomous comparative variables, a Chi Square Test were used. Results: The mean age of the whole studied OIC affected patients was 58.94±10.37 years. The overall 28-day ICU mortality was detected in 76 patients with an overall incidence rate of 40.4% during an average of 12.76±4.95 days of ICU admission days. Group I had a significantly higher total calories input and protein density input compared to Group II (1265.53±245.95 Cal/day and 4.85±0.71 g/100 Cal vs 1155.25±228.36 Cal/day and 3.90±0.55 g/100 Cal, respectively, p<0.05). Conclusion: Our study showed that the investigated soluble fiber, in the form of FOS 1.7 gram/30 ml, may be an innovative strategy in mitigation of an opioid analgosedative related inevitable negative clinical impacts.