Treatment
CQ 3-1.An RCT comparing the efficacy of soluble fiber
(psyllium, ispaghula), insoluble fiber (bran), and
placebo in IBS patients revealed that soluble fiber
significantly improved abdominal pain and discomfort
compared with placebo [94].In western coun-
tries, several RCTs have revealed that a low fer-

mentable, oligosaccharides, disaccharides,
monosaccharides, and polyols (FODMAP) diet appears
to be more effective than standard dietary advice for
IBS patients [87, 88].The utility of probiotics in the treatment of IBS has
been investigated in a large number of intervention
studies including many high-quality systematic
reviews, meta-analyses, and RCTs [113-122], but the
results were somewhat inconsistent.With regard to dopamine D2
blocking agents, small-scale RCTs [106, 107] investi-
gated the efficacy of domperidone in IBS patients and
found no beneficial effect of this agent on gastroin-
testinal symptoms.In other countries, several
small-scale RCTs [108-110] and meta-analyses
[103, 111] of anticholinergic agents indicate that
anticholinergic agents are effective in improving gas-
trointestinal symptoms including abdominal pain,
although some reports do not appear to show improve-
ment in overall symptoms [104, 112].In addition, a
systematic review of 14 randomized studies reported
that 1 h of yoga every day for 4 weeks, 0.5 h of
walking almost every day for 12 weeks, and 0.5 to 1 h
of aerobic exercise significantly improved IBS symp-
toms [91].The efficacy of trimebu-
tine maleate in patients with IBS was investigated in
several small-scale RCTs [98-101] and meta-analyses
[102, 103] conducted overseas.o Eliminating foods that exacerbate IBS symptoms,
such as lipids, caffeine, spicy food, and milk and
dairy products, is effective in managing IBS.It functions
under acidic conditions as soluble fiber by absorbing
water and thus potentially improving stool consistency
[92].In Japan, tiquizium bromide,
butylscopolamine bromide, timepidium bromide
hydrate, and mepenzolate bromide have all been used
as anticholinergic agents for the treatment of abdominal
symptoms in IBS patients.If
symptoms worsen after taking a particular meal,
eliminating culprit foods from the diet is necessary,
such as foods with high-fat content, caffeine, spicy foods, and milk and dairy products.In a Japanese phase III randomized controlled
study, polycarbophil calcium was superior to trimebu-
tine maleate in efficacy and equal in safety [93].This discrep-
ancy in results may be attributable to methodological
differences among trials, such as the type of probiotic
used, duration of treatment, and outcome.This drug appears to
improve gastrointestinal symptoms including abdomi-
nal pain in IBS patients, although no overall improve-
ment was observed.Comment: Trimebutine maleate acts on the peripheral l
and j opioid receptors [96] and is a representative
gastrointestinal modifier [97].Also, no clinical evi-
dence is available on the efficacy of neostigmine or
itopride in IBS patients.Some studies with
probiotics versus placebo found an improvement in
global symptoms with probiotics, while others failed to
demonstrate a clear effect of probiotics.Comment: Twelve weeks of exercise significantly
improved the symptoms and extraintestinal manifesta-
tions of IBS in 102 patients [89].CQ 3-2.