Comparison of the Effectiveness of Magnesium Oxide and Elobixibat on Improving Rectal Sensitivity and Colonic Transit Time in Patients With Chronic Constipation: An Observational Study

ABSTRACT Background We compared the effectiveness of magnesium oxide (MgO) and elobixibat (EXB) in improving defecation desire (DD), rectal sensation, and colonic transit time (CTT) in patients with chronic constipation (CC). Methods This was a prospective, observational study conducted in real‐world clinical practice. We included patients with CC who met the Rome IV criteria and underwent colon transit study and rectal sensory tests ( RSTs ). Loss of defecation desire (LODD) was subjectively assessed using a questionnaire, and the rectal sensation was objectively assessed using the balloon air volume, which was measured using the first defecation desire volume (FDDV). CTT was measured using radiopaque markers, and slow transit constipation (STC) and normal transit constipation (NTC) were diagnosed using marker residual rate. The shift rate from STC at baseline to NTC after each drug administration was calculated. Drugs were selected at the discretion of the attending physician. Key Results Patients in the MgO ( n = 30) and EXB ( n = 43) groups had comparable demographic characteristics, an average prescription duration of 27 days, and average daily dosages of 1413 and 13 mg, respectively. Patients in the MgO and EXB groups showed different improvement rate of LODD (33% vs. 65%, p < 0.001), absolute changes in FDDV (−0.1 vs. 35 mL, p < 0.0001), and shift rate from STC to NTC (37% vs. 87%, p = 0.003, respectively). Conclusions and Inferences EXB demonstrated significantly greater improvements of LODD, rectal sensation, and CTT compared to MgO.