Positron Emission Tomography-Computed Tomography (PET-CT) was introduced over four decades ago as an imaging tool to evaluate functional and anatomical aspects of disease such as malignancy. Besides pathological uptake, PET-CT also shows physiological uptake, especially in the gastrointestinal system, thus impacting diagnostic accuracy in these cases. There are many conditions that can attribute to increasing physiological uptake in PET-CT including microbial activity and drugs. Therefore, certain anti-spasmodic agents have been introduced to help reduce physiological uptake during scanning such as Hyoscine-n-butylbromide (Buscopan). This study aims to establish its effectiveness in reducing physiological bowel uptake on 18F-FDG PET-CT scan. Methods: 133 subjects were recruited in random for this study and divided into hyoscine (68 subjects) and control groups (65 subjects), respectively. Subjects in control group not given any anti-spasmodic medications and both groups received intravenous 18F-FDG according to body weight. PET-CT scan and images were interpreted by experienced nuclear medicine physician who scored the images according to the degree of bowel uptake and difficulty of image interpretation. Results: There were no statistical difference in bowel uptake based on SUV mean of the bowel and bowel-to-liver ratio between hyoscine and control groups. Conclusion: There was no significant effect of Hyoscine-n-butylbromide in reducing physiological bowel uptake in PET-CT scan.