Table 2.
Purgative regimens: efficacy, tolerability, and practical considerations.
| Regimen | Volume | Adequate preparation/BBPS | Tolerability | Notes |
|---|---|---|---|---|
| 4-L PEG | 4 L | Adequate cleansing 97.1% in Dutch screening (2) | Nausea, bloating, lower completion rates (33) | Gold standard for safety/effectiveness; high volume limits tolerability (2, 33) |
| 2-L PEG-ASC | 2 L | Adequate cleansing 98.0% (2) | Generally better tolerated than 4-L PEG | Met ESGE minimum standard (BBPS ≥6); significantly higher adequate cleansing than 4-L and ≤1-L (2) |
| 1-L PEG-ASC/NER1006 | 1 L (total fluid 1,500–2,000mL) | Cleansing success 90.1% vs 4-L 72.4% and 2-L 74.1%; high-quality right-colon cleansing 41.4% vs 15.9% and 12.0% (56) | Mild-to-moderate adverse events slightly more than conventional in meta-analysis; less bloating/nausea due to lower volume (56, 57) | Meta-analyses confirm superior overall and right-colon cleansing (57); US real-world survey: 89.9% satisfied/very satisfied (58) |
| 1-L PEG-ASC in IBD/UC | 1 L, split-dose; total fluid 1,500–2,000mL | IBD overall cleansing success 94.2% (28); 1 L PEG-ASC vs 2 L PEG: 89.8% vs 83.8%, median BBPS 8 vs 6 (23); UC: 1 L vs 3 L PEG BBPS 6.80 ± 1.57 vs 7.24 ± 1.43, non-inferior (30); split 1 L PEG: BBPS ≥6 in 85.4% (31); meta-analysis low- vs high-volume PEG: RR 0.98 (29) | Better tolerated than higher-volume PEG; less nausea; higher willingness to repeat (28, 30, 31); severe nausea only 0.3% (28) | Split-dose low-volume PEG, especially 1 L PEG-ASC, is generally preferred in IBD/UC; avoid sodium phosphate in severe colitis or renal impairment (23, 26, 28–32) |
| SPMC | Low-volume (product-dependent) | Comparable efficacy to PEG in pediatric study; favorable profile across age groups including ≥65 years; consistent efficacy/tolerability across BMI groups (11, 33, 59) | Better palatability and acceptability than PEG; suitable for patients unable to tolerate large-volume PEG (33, 59) | Often compared with 1-L PEG-ASC; broadly comparable adequate preparation rates, but 1-L PEG-ASC may provide superior right-colon cleansing in some trials (33, 56, 59)；head-to-head comparisons also include (60, 61) |
| Lactulose | Low-volume (regimen-dependent) | Non-inferior to PEG for overall cleansing in several RCTs/meta-analyses, largely Eastern populations (34) | Less nausea and bloating; more abdominal cramping; longer preparation-to-colonoscopy intervals (34) | Consider for patients who cannot tolerate PEG; guideline endorsement remains limited (34); see also (62, 63) |
| Sulfate tablets (OST) | 24 tablets with adequate fluid | Non-inferior cleansing to PEG-ASC (64) | Good tolerability (64) | Novel tablet formulation; avoids large-volume liquid (64) |