Brief Articles
Copyright ©2009 The WJG Press and Baishideng.
World J Gastroenterol. Jun 28, 2009; 15(24): 3032-3037
Published online Jun 28, 2009. doi: 10.3748/wjg.15.3032
Table 1 Inclusion and exclusion criteria
Inclusion criteria
Adults aged 18-70 years of age scheduled for colonoscopy at the gastroenterological unit
Exclusion criteria
Renal insufficiency (Cr ≥ 2 mg/dL)
Uncontrolled congestive heart failure (NYHC III-IV)
Massive ascites
Myocardial infarction within 6 mo
Pregnancy
Coagulopathy
History of colonic surgery
Colonic obstruction
History of anti-flatulence and/or other laxative agent use within 1 wk
Refusal to participate in the study
Table 2 Baseline characteristics of the study groups (%)
CharacteristicsSimethiconePlacebo
n= 62n= 60
Age (yr); mean (SD)57.5 (9.9)56.5 (11.7)
Gender
Male27 (43.5)23 (37.1)
Female35 (56.6)37 (61.7)
Indication for colonoscopy
Screening25 (40.3)26 (43.3)
Symptomatic37 (59.7)34 (56.7)
Underlying diseases
Diabetic14 (22.6)12 (20.0)
Hypertension17 (27.4)16 (26.7)
Coronary artery disease2 (3.2)3 (5.0)
Liver disease10 (16.1)5 (8.3)
Malignancy5 (8.1)8 (13.3)
GI disease7 (11.3)3 (5.0)
No underlying disease18 (29.0)22 (36.7)
Medication
Antihypertensive agent19 (30.7)20 (33.3)
Hypoglycemic agent12 (19.4)11 (18.3)
Antiplatelet4 (6.5)7 (11.7)
No medication25 (40.3)27 (45.0)
Table 3 Colonoscopic results, endoscopic visibility and procedure time between the study groups (%)
SimethiconePlacebo
n = 61n = 59
Endoscopic findings
Normal17 (27.4)16 (26.7)
Polyps31 (50.0)28 (46.7)
Cancer1 (1.6)3 (5)
Colitis4 (6.5)7 (11.7)
Nonspecific2 (3.2)2 (3.3)
Others7 (11.3)4 (6.7)
Degree of air bubbles
Acceptable61 (100.0)25 (42.4)b
Cecum60 (98.4)38 (64.4)b
Ascending colon59 (96.7)32 (54.2)b
Transverse colon60 (98.4)30 (50.8)b
Descending colon59 (96.7)30 (50.8)b
Rectosigmoid colon61 (100.0)46 (78.0)b
Unacceptable034 (57.6)
Adequacy of colon preparation
Acceptable  55 (90.2)48 (81.4)
Unacceptable  6 (9.8)11 (18.6)
Duration of colonoscopy (min); mean (SD)25.1 (13.2)27.3 (13.0)
Table 4 Endoscopist and patient satisfaction for bowel preparation (%)
SimethiconePlacebo
n = 61n = 59
Endoscopist satisfaction
Air bubble48 (79.0)19 (32.8)a
Adequacy of colon preparation42 (68.9)33 (55.9)
Patient satisfaction; mean (SD)8.7 (1.8)7.6 (1.9)b
Table 5 Side effects of bowel preparation (%)
SymptomsSimethiconePlacebo
n = 40n= 43
Nausea and vomiting12 (30.0)16 (37.2)
Abdominal pain5 (12.5)6 (14.0)
Fatigue2 (5.0)1 (2.3)
Sleep disturbance01 (2.3)