The optimal protocol for small bowel (SB) cleansing in capsule endoscopy (CE) remains controversial. This study aimed to evaluate differences in SB cleansing quality between two low-volume polyethylene glycol (PEG) regimens.

Patients eligible for CE were prospectively enrolled in this single-center, open-label study. All patients followed a low-fiber diet for three days and fasted for 12 hours prior to CE. They were randomly assigned to receive either 1 L of PEG 12 hours before CE (Group A) or 1 L of PEG 3 hours before CE (Group B). All CEs were reviewed by a single endoscopist. SB transit times (SBTT) were measured. Patients tolerability and side effects PEG related were recorded. SB cleanliness was assessed using the Small Bowel Cleansing Assessment and Report (SB-Clear) score and the Brotz score.

Between October 2024 and October 2025, 29 consecutive patients were prospectively enrolled. Thirteen patients (44.8%) were randomly assigned to group A, sixteen patients (55.2%) to group B. 55.2% were males, 69% were outpatients. The main indication to CE was obscure gastro-intestinal bleeding (16 patients, 55.2%). No differences in compliance of the two PEG regimens were found; all patients received the whole volume of PEG without side effects. The main lesions observed were vascular ones (13 patients, 44.8%).

There were no statistically significant differences in age (mean 65.4 ± 18.4 SD group A vs 55.1 ± 21.9 SD group B) and sex between the two groups. Overall SB cleansing was adeguate in 27 patients (93.1%). Cleansing scores were significantly higher in group B (SB-CLEAR mean 7.38 ± 0.9 SD vs 6.38 ± 1.4 SD, t-test p=0.04; Brotz QI mean 6.18 ± 1.2 SD vs 5.07 ± 0.6 SD, t-test p=0.008), no differences were found in Brotz QE and overall adequacy assessment (OAA). No statistically significant correlations were found among SBTT and SB cleansing scores, even if in Group 2 a shorter SBTT was correlated to higher quality SB cleansing scores (SB-CLEAR Pearson r -0.220 p=0.412; Brotz QI Pearson r -0.209 p=0.437). No statistically significant differences were found between detection of vascular lesions and SB cleansing scores. Multivariate analysis were no reliable because of small sample size.

A low-volume, same-day PEG regimen is associated with improved small bowel cleansing scores compared with a day-before PEG regimen.