Constipation - The Gut Foundation

Constipation and Bloating v5
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Constipation
and
Bloating
Revised in 2006 by
Mr John Bell
Professor Terry Bolin
Dr Alistair Cowen
Dr John Gullotta
Ms Geraldine Georgeou
Professor John Kellow
Professor Mel Korman
Dr Fiona Nicholson
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Introduction
Constipation is common and almost one
person in five over the age of 30 has
constipation at some stage during their life.
Constipation refers to the consistency of
the stools and any difficulty in passing
them, as well as the frequency of bowel
movements. Normal bowel function ranges
from one to two stools a day to one stool
every three to four days. Not everyone who
has infrequent stools will have other
symptoms of constipation such as bloating
or discomfort.
The medical definition of constipation is
the infrequent passage of small or hard
stools with or without straining.
What an individual believes is constipation
may not match this definition. Symptoms
commonly reported as constipation
include:
• Straining
• Hard or lumpy stools
• Incomplete evacuation
• Unproductive calls to stool
• Abdominal bloating/distension
• Infrequent stools
Straining and difficulty in emptying the
rectum are common complaints even if the
stools are not hard and two to three bowel
actions occur per day. This is particularly
true in women who may have had a
difficult or complicated labour during
childbirth resulting in pelvic muscle
weakness. Constipation is common in the
elderly of either sex.
Boys predominate in early childhood
constipation; in teenage and young adults
it becomes a predominantly female
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problem; in old age gender equality is
achieved.
Constipation can be associated with
specific diseases (eg thyroid under activity,
colon cancer) but by far the commonest
form is simple constipation related mainly
to diet and age.
It is a significant problem in communities
where fibre intake is low, but is virtually
unknown when the diet is high in fibre.
Constipation is common among residents
of nursing homes where the diet is
generally low in fibre. In communities
where there have been campaigns to
promote high fibre food such as wholemeal
bread, constipation and laxative use have
been substantially reduced.
The typical Australian diet does not contain
the minimum recommended 30g of fibre
needed for normal bowel movements.
When fibre is increased to this level or
above there are fewer cases of
constipation.
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This is compounded by an often limited
understanding of the best sources of fibre
in the diet. For example if you do not eat
breakfast cereal high in fibre then it is
unlikely that you will achieve the suggested
dietary fibre intake during the remainder of
day.
The most obvious effect of dietary fibre is
on stool bulk. On a western diet the
average stool weight is about 100-150g
per day. In vegetarians this increases to
about 225g per day. Daily faecal weight for
rural Africans eating very high fibre diets
may be 400g or more.
The amount of fibre in the diet is also
correlated with the intestinal transit time.
On a typical low fibre western diet transit
from mouth to anus is 24-36 hours. It can
be even longer and some studies in
western society where fibre intake is very
low have shown transit times of 60 hours.
In contrast, Rural Africans with very high
fibre content in their diet, have transit times
as low as 12 hours.
It is important to recognize that
constipation is only a symptom and
however it is defined it can have many
causes. Most people will experience
transient changes in bowel habit. Transient
constipation can be related to changes in
diet, travel, painkillers and no investigation
is required provided the bowel habit
returns to normal. In adults over the age of
40 a persistent change in bowel habit –
usually constipation – requires investigation
to exclude bowel cancer. Any change of
bowel habit in an adult associated with
rectal bleeding requires colonoscopy and
identification of the source of bleeding.
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Bloating
Bloating is a common
problem, especially in
women.
It usually consists of distension of the
lower abdomen, so that while the abdomen
might be flat in the morning, by the end of
the day it is distended and uncomfortable,
often requiring a change of clothes to
something looser. It may or may not be
accompanied by constipation. The
distension is often aggravated by high fibre
foods which generate gas. Women with the
complaint of bloating have a bowel that is
easier to distend and this gives the
appearance of containing more gas.
Muscular activity in the gut and muscle
contraction in the walls of blood vessels
are regulated by a special part of the
nervous system called the autonomic
nervous system. In women with bloating
there is an alteration in the nerves which
sense distension and nerves which control
gut contraction. These changes make it
harder to pass flatus and cause abdominal
pain. Women with bloating frequently suffer
cold fingers which go white or blue in
winter as a result of similar changes in
blood vessel contraction.
As bloating may accompany a high fibre
diet, any increase in fibre intake should be
gradual to allow time for the gut to ‘get
used to’ the increased volume of gas
produced.
Before we consider the various types of
constipation and how they may best be
treated it is important to have an
understanding of digestion.
See Appendix 1
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Types of
constipation
Constipation is often separated into four
groups. This may be helpful in prescribing
treatment but there is significant
overlapping of groups.
The best indicator of constipation is the
consistency of the stool; that is whether it is
small and hard or looser as outlined in the
following table:
Constipation descriptions
Bristol Stool Form Scale
Type 1 Separate hard lumps, like nuts
Hard
Type 2 Sausage-like but lumpy
Type 3 Like a sausage but with cracks in
the surface
Type 4 Like a sausage or snake, smooth
and soft
Normal
Type 5 Soft blobs with clear-cut edges
Type 6 Fluffy pieces with ragged edges,
a mushy stool
Type 7 Watery, no solid pieces
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Loose
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The types of constipation are as follows:
Functional Constipation
Simple
constipation
Irritable bowel
syndrome with
constipation
Disease Associated
Constipation:
1.
Diseases which affect nerve function.
Eg Thyroid under activity, Parkinson’s
Disease, Diabetes and Scleroderma
2.
Diseases which obstruct flow of the
stool. Eg Bowel Cancer, Diverticular
Disease, strictures
3.
Drugs which affect bowel function.
Eg Morphine, Pethidine, Codeine,
Antidepressants, Iron preparations.
There is usually, but not always a definite
cause for the sudden onset of
constipation. Drugs are an important
cause. Analgesics, especially Panadol/
codeine preparations such as Panadeine
may cause severe constipation even in
small doses. Sudden recent constipation in
adults always requires investigation. This
will usually include colonoscopy to rule out
the serious causes above.
Functional Constipation:
A. Simple Constipation:
Many people will suffer from occasional
constipation. This is the most common
form of constipation – simple constipation.
Travel, stress, dietary change or altered
work patterns interrupt an otherwise
regular bowel pattern. Provided there are
no serious accompanying symptoms (such
as rectal bleeding) no investigation is
Disease Associated
Constipation
Slow transit
constipation
Defaecation
disorders
required. Recognizing the cause of the
change in pattern and correcting it where
possible may be enough. For example,
make some dietary changes when traveling.
In simple constipation, the first and usually
the only step required, is to ensure an
adequate intake of dietary fibre from a
wide variety of sources, including fruits and
vegetables and wholegrain products. Many
people who think they are eating a highfibre diet do not reach the levels of fibre
needed to prevent constipation. If
constipation persists, a bulking agent
should also be used. Laxatives are a useful
option if simple dietary and fluid measures
are unsatisfactory.
When constipation does not respond to
simple measures, it is important to exclude
constipation associated with disease. This
will probably require examination of the
colon. Some people with severe
constipation will need to be referred to a
gastroenterologist or colorectal surgeon
with a special interest in constipation.
Motility tests and electromyography may
be necessary to study colonic transit and
pelvic floor function.
For Australians of all ages, and especially
women, constipation is so common that
everyone needs to know how to achieve a
high-fibre intake before resorting to
laxatives. If constipation persists after
achieving an adequate dietary intake of
fibre and adding a stool bulking agent then
long term laxatives may be required.
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The type of laxative chosen should fit the
stool type. For example, where the stools
are extremely hard a stool softener should
be added first. Often an osmotic or
stimulant laxative will also be required.
(See Laxative chart) Some experts believe
that laxatives with high anthraquinone
content should be avoided for long term
use. It is stressed that adequate dietary
fibre intake and bulking agents should
be used before laxatives.
Equally when the response has been
inadequate, sensible long term use of
simple laxatives will not cause harm and
can greatly improve quality of life.
Many women relate the onset of
constipation to uncomplicated surgery
such as hysterectomy or appendicectomy,
or it may follow a normal pregnancy. In
teenage years, the excessive use of
laxatives for weight loss may be the trigger.
B. Irritable Bowel Syndrome with
constipation (IBS-C):
In contrast to simple constipation this is
usually associated with abdominal pain or
discomfort. The pain often improves
following defaecation or passage of wind.
It is usually in the lower abdomen and
frequently worse on the left side.
In IBS there may be a fluctuating pattern of
bowel habit, with the motions sometimes
being hard or lumpy and at other times loose.
There is a predominance of this problem in
the female population and there may be a
change in the pattern of symptoms at the
time of menstruation. Irritable bowel
symptoms commonly begin in the 15-30
age range. About one quarter of Irritable
Bowel sufferers find that the problem
develops after a severe bout of infectious
diarrhoea. When Irritable Bowel-like
symptoms occur for the first time after the
age of 40, colonoscopy is required to
exclude bowel cancer and other serious
colon problems.
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Treatment of Irritable Bowel Syndrome may
vary with the predominant symptom.
Dietary fibre needs to be introduced with
care. Some high fibre products, for example
unprocessed bran may make symptoms
worse (see discussion on dietary fibre).
Dietary manipulation is often best
undertaken with the help of an experienced
dietitian. Frequently medication will be
helpful. Antispasmodics, for example
Colofac, can be helpful and may need to
be taken on a long term basis. Resistant
symptoms may require addition of a
tricyclic antidepressant. These drugs are
not used for their anti-depressant effect
but for other actions on the neuromuscular
bowel function. They can often be effective
in small doses well below antidepressant
dosage. Where constipation is a major
component, Zelmac (Tegaserod) is often
beneficial particularly in women.
C. Slow Transit constipation:
A wide range of constipation problems are
included within this group. Some people
have a life long pattern of sluggish bowel
habit with movements only every 2 to 3
days. There is increasing evidence that
constipation exists because of a
combination of poor muscular contraction,
abnormalities of gut hormones, or both.
This may cause a slow gut transit time,
which can be measured by swallowing
radio-opaque markers and then having a
plain x-ray of the abdomen. Severe
constipation present from birth requires
investigation to exclude Hirschsprung’s
disease.
A small group of women begin to
experience progressively severe
constipation in the late teens or twenties.
Without laxative stimulation bowel actions
may occur only every 1 to 2 weeks.
Abdominal pain, distention, nausea and
headache may develop after a prolonged
time without a bowel action.
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Investigations may show an apparently
normal colon with slow transit. However a
small number will have a true
“Megacolon”, defined as a colon which is
twice as long and twice as wide as usual.
Treatment can be difficult. Those with an
apparently normal colon can usually be
managed with a combination of laxatives
and/or Zelmac.
Patients with true Megacolon must avoid
laxatives with a high anthraquinone
content. Management requires a
combination of multiple laxatives with
different modes of action. Increasing fibre
in the diet is usually counterproductive for
Megacolon patients. Symptoms of
bloating, excess wind and pain are often
more severe on a high fibre diet.
Surgery is usually not indicated in patients
with slow transit constipation, although it
can be considered in very severe cases.
Likewise, SURGERY FOR MEGACOLON IS
TO BE AVOIDED IF POSSIBLE. IT MUST
NEVER BE UNDERTAKEN BY ANYONE
OTHER THAN A COLORECTAL SURGEON
WITH SPECIAL EXPERTISE IN THIS
DISORDER AND ONLY AFTER A FULL
INVESTIGATION. This will include
colonoscopy, transit studies, anorectal
physiological studies and if necessary
pelvic floor nerve conduction studies.
D. Defaecation disorders:
In those who have anal sphincter
dysfunction or disturbance of pelvic floor
muscles, the major problem is in
evacuating the rectum. This may be a
function of increasing age, follow a
complicated vaginal delivery, anorectal
surgery or a Rectocoele (where the rectum
protrudes into the vagina). When this is
severe it may be necessary to manually
empty the rectum or press on the rectum
through the vagina to help defaecation.
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There are a variety of measurements that
may be undertaken by a specialist to
confirm this problem. These may include
rectal balloon expulsion tests that give an
indication of the type of problem that is
involved. Measurement of muscle and
nerve function can also confirm the
inadequate forces present to propel faeces
from the rectum. Behavioural therapy to
improve the technique of defaecation
(anorectal biofeedback therapy) is available
in some specialised centres and can lead
to symptom improvement in particular
types of defaecation disorders
Operations to repair Rectocoele can be
very helpful. However it is important to
exclude other contributory factors. Where
multiple problems including poor pelvic
muscle function and poor rectal sensation
are present, simple operative repair of the
Rectocoele may not achieve useful
improvement.
The Role of
Dietary Fibre
in the treatment
of constipation:
The process of digestion and the important
role of dietary fibre are now better
understood. Recent studies have also
shown that some types of starch, known
as resistant starch, are at least as
important as dietary fibre. Both fibre and
starch play an active part in the health of
the colon.
Good food and better nutrition are
fundamental to gastrointestinal health. The
wide range of fruits, vegetables, grains,
breads, cereals, nuts and seeds which
contain dietary fibre may also have
important protective effects against many
diseases, including bowel cancer. Fibre is
much more than the old idea of roughage.
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The physical presence of fibre in the bowel
is important but there is extra value from
dietary fibre. When fibre and resistant
starches reach the colon, they are broken
down by bacteria. During this process,
volatile fatty acids are produced. One of
these acids – butyric acid – helps keep the
cells in the walls of the colon healthy.
Dietary fibres can be characterized as
soluble or insoluble.
Many people restrict high-fibre foods
because of fears about flatus.
Fermentation of dietary fibre and resistant
starch by helpful bacteria does produce
gases, but unless this is excessive, it is a
normal process and the slight social
inconvenience is a small price to pay for
eating a nutritious diet.
— mucilages (in seeds and bulking
supplements)
What is dietary fibre?
Dietary Fibre is defined as the remains of
the edible part of plants and other
carbohydrates that are not digested in the
small intestine but pass to the large bowel
(colon) where most are completely or
partially broken down by bacteria. Fibre
includes lignin and polysaccharides as well
as natural waxy substances found in food.
The plant materials which make up dietary
fibre are diverse and difficult to define and
measure. Once they reach the large bowel,
some, such as pectin and most gums, are
totally fermented. Others, such as
cellulose, are broken down to varying
degrees in different individuals. Lignin is
not digested at all.
Starches known as ‘resistant starch’
escape digestion in the small intestine and
are broken down by bacteria in the colon.
When bacteria break down dietary fibre
and resistant starch, they multiply in the
process and contribute to the bulkiness of
faeces.
The fermentation process also produces
volatile fatty acids which play an important
role in bowel health.
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Soluble Fibres:
— pectins (in fruits and seeds)
— hemicelluloses (in cereals, fruits and
nuts)
— gums (in seeds, cereals and as a food
additive)
Insoluble Fibres:
— lignin (in wheat bran, legumes,
vegetables and some fruits)
— cellulose (in vegetables, legumes,
cereals, fruits and nuts)
Resistant Starch:
Starches are made up of many glucose
units. Whether starches are digested in the
small or large intestine depends on the
structure of the starch, the structure of the
starchy food itself, the presence of plant
cell walls, linkages with proteins or fats,
and the type of heat used in processing or
cooking.
Cooking and subsequent cooling,
reheating and processing may also alter
the site where starches are broken down.
For example, the starch in a hot potato is
digested by enzymes in the small intestine
whereas the starch in the same potato
allowed to cool, alters its structural
alignment and resists being broken down
by enzymes, passing instead to the large
bowel as ‘resistant starch’.
The way rice is cooked also alters its
starch and the amount that enters the
colon as resistant starch. Rice cooked by
the Asian absorption method, in which only
sufficient water is used and is totally
absorbed by the rice, has more resistant
starch than rice cooked in a large volume
of water and then drained.
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Fermentation of resistant starch in the large
bowel may produce much greater
quantities of valuable volatile fatty acids
than dietary fibre. Resistant starch may be
therefore at least as important as dietary
fibre.
Effects of Dietary Fibre:
Faecal bulk:
Faeces consist of approximately 75%
water and 25% dry matter. The dry matter
is made up of undigested residues plus
bacteria and the debris of bacterial cells.
Dietary fibre contributes to faecal bulk in
different ways.
Lignin passes through the intestine
unchanged and increases faecal bulk by its
physical presence and by its ability to hold
water. Soluble fibres, such as pectin in
fruits, hemicelluloses in vegetables, and
gums and mucilages in oats, seeds and
some fruits increase the population of
bacteria, and thus the bacterial content of
the faeces. Some cellulose is broken down
by bacteria and increases bacterial bulk;
some is undigested and absorbs water to
increase faecal weight.
Resistant starch leads to increased
bacterial mass and is therefore an
important contributor to faecal bulk. This
may be significant, especially in those
whose diets are high in rice which has
been cooked in such a way that it has a
high content of resistant starch, as
described earlier.
A high fibre diet contributes to an
increased bulk of stool not only by
undigested fibre but largely by increasing
the bacterial mass. In the normal colon
there may be one to two kilograms of
bacteria. There are at least 400 different
species of bacteria and this becomes
important to remember when we talk about
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other therapies including pre-biotics and
probiotics and how they influence colonic
function.
Volatile Fatty acids:
The short chain volatile fatty acids –
butyric, propionic and acetic acids,
produced when bacteria ferment dietary
fibre and resistant starch have a number of
functions. Butyric acid may give protection
against colon cancer.
Propionic acid may stimulate muscular
activity in the colon. Each of the volatile
fatty acids is available as an energy source
for the cells of the colon. They also provide
a source of energy for the rest of the body,
currently thought to be 2 – 3 calories per
gram.
Soluble fibres ferment rapidly in the right
colon (also known as the proximal colon);
insoluble fibres ferment more slowly during
their transit throughout the entire length of
the colon.
Rate of Digestion:
Soluble fibres form viscous gels which may
trap nutrients, digestive enzymes or bile
acids. This can slow down the rate at
which sugars are digested and absorbed,
and can have favourable effects on blood
glucose in people with diabetes. Gummy
fibres, pectin and resistant starch can also
help control blood sugar levels. Whole
grains in products such as bread also slow
down the rate of digestion and help control
blood sugar levels.
Satiety (or feeling full after eating):
High-fibre foods produce greater bulk in
the stomach, increasing the feeling of
fullness. Foods high in soluble, viscous
fibres have a greater effect in this respect
than insoluble fibres.
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Eating more foods rich in soluble fibre may
therefore give greater satiety than insoluble
fibre. It makes sense to eat less fat and
more foods high in all types of dietary fibre.
Serum cholesterol levels:
The ability of dietary fibre to reduce blood
cholesterol is small and reducing saturated
fat is the best way to control blood
cholesterol. Many types of fibre have no
effect on cholesterol, but some viscous
soluble fibres from pectins, and beta
glucans in oats and barley, can restrict the
amount of cholesterol and bile acids
absorbed from the small intestine and
therefore lower blood cholesterol levels.
How Fibre
Affects Faecal
Bulk:
The most obvious short-term effect of
dietary fibre is on the stool bulk. This
involves:
1.
Lignin and some cellulose passing
through the colon unchanged. These
forms of dietary fibre increase stool
weight by their own mass and by their
ability to hold water. Wheat bran has a
high content of lignin and cellulose.
2.
Soluble fibres (pectins,
hemicelluloses, gums and mucilages)
and resistant starch stimulate the
growth of bacteria which then increase
stool volume. Oats, legumes, fruit and
vegetables are sources of soluble
fibres and resistant starches are also
found in oats, other grains, legumes
and some types of bread flour.
There is also a close correlation between
stool bulk and transit time through the gut.
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In general, the greater the bulk, the shorter
the transit time.
Dietary Fibre
and Flatulence
Between 500 and 2500ml of flatus is
produced every 24 hours. There are no
reports of significant differences in the
volumes generated by men and women.
However, men report more emissions than
women (12 times a day for men and 7
times a day for women; with a range for
both sexes of between 2 and 30).
The number of emissions depends on the
fibre content of the diet, with higher fibre
levels generating more flatus. The usual
emission volume is about 90ml. There is
little relationship between the number of
times a person passes flatus and the total
volume, suggesting that the size of
emissions varies among individuals
because of different sensitivities to
gaseous distension of the rectum.
The amount of flatus produced varies
widely throughout the day and night. Some
people produce greater volumes in the
morning, others in the evening. Larger
volumes tend to follow meals. Less is
produced during sleep.
Foods and Flatus:
Some people are unwilling to consume
enough dietary fibre to avoid problems
such as constipation because they are
worried about flatus.
It is true that the more fibre consumed the
more gas produced. It is also true that
some foods are more potent sources of
gas than others. Vegetables such as
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onions, legumes (dried beans and peas)
and brassicas (cauliflower, Brussels
sprouts, cabbage and broccoli) are
common culprits. Some people find that
other foods also give them extra flatus.
However, production of gas is normal and
the major problem is social
embarrassment.
In those with a deficiency of lactase, the
natural sugar (lactose) in milk ferments. If
more than a small glass of milk is
consumed, there may be a lot of gas
accompanied by abdominal distension
and, sometimes pain.
Fructose is an important sugar component
of many fruits. Apples and Pears,
particularly as juices, contain a lot of
fructose and can produce gas and
discomfort if eaten to excess. Fructose is
also present in honey and is often used as
a sweetening agent.
Sugar alcohols such as sorbitol, mannitol,
maltitol and xylitol, sometimes used as
sugar substitutes in calorie-reduced
confectionery, low-kilojoule jellies and
other foods can also cause problems. At
least half the population is intolerant to a
10 gram dose of sorbitol – the amount in 4
or 5 sorbitol-containing mints or a
tablespoon of some carbohydrate-modified
jams. Sorbitol is also a natural ingredient in
apples and pears and excessive
consumption of these fruits – usually as
juice – may increase flatus. Some
medicinal syrups, multivitamins,
expectorants and bronchodilators may also
include sorbitol.
Dietary Fibre:
Are you getting
the right amount?
What is your daily fibre intake? Total…………g/day
Breads, Grains, Cereals
High Fibre Mixed
Grain Bread(1 slice)
Bread, white (1 slice)
1.6g–3.0g
1.0g
Bread, wholemeal (1 slice) ~4.0g
High fibre cereal
Low fibre cereal
(eg: rice bubbles)
Tick
Tick
4.0g–11g
0g
Muesli (50g)
6.0g
Bran (15g)
7.0g
Pasta (100g dry)
5.0g
Rice (white, 1 cup cooked)
2.0g
Brown Rice (1 cup cooked) 3.0g
Pasta (1 cup cooked)
3.0g
Pasta wholemeal
(1 cup cooked)
9.0g
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Vegetables and Legumes
Beans (green) 1 cup raw
Tick
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Nuts and Seeds
Tick
3.0g
Almonds (50g)
4.0g
Kidney beans (100g canned) 7.0g
Cashews (50g)
3.0g
Asparagus (100g canned)
4.0g
Peanuts (50g)
4.0g
Broccoli (100g raw)
4.0g
Sunflower (1 tbsp)
1.5g
Carrots (1/2 cup raw)
2.0g
Pumpkin seeds (50g)
Cabbage (1 cup raw)
1.0g
Other nuts (100g)
Corn on the cob
3.0g
12.5g
7.0g
Cucumber (1 whole-unpeeled) 1.0g
Fresh Fruit
Lentils (100g boiled)
4.0g
Apple
3.0g*
Potato (medium, unpeeled)
3.0g
Pear
3.0g
Spinach (100g raw)
3.0g
Banana
3.0g
Kiwi fruit
3.0g
Orange
3.0g
Other fruit (100g)
3.0g
Other vegetable (1 cup)
5g -8g
Dried Fruits
Tick
Apricots (50g)
4.5g
Sultanas (50g)
2.0g
Figs (50g dried)
7.0g
Coconut (50g dried)
7.0g
How did you do? Australian adults are
encouraged to consume more than 30
grams of fibre a day.
Since wholegrain cereals have been
associated with a lower risk of
cardiovascular disease, bowel cancer and
assisting with stabilizing glucose control in
Diabetes, nutritionists including the
National Heart Foundation of Australia (Feb
2006 National Heart Foundation of
Australia Position Statement
Carbohydrates, dietary fibre, glycaemic
index/load and cardiovascular disease)
recommend that as part of your total fibre
intake you should consume at least 6
grams of wholegrain fibre per day.
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Tick
In food terms this is equivalent to 3 to 4
slices (100 g) of wholegrain bread, or 2
slices of wholegrain bread and a serve of
wholegrain cereal. Wholegrain bread is
bread made from whole or kibbled grains,
wholemeal or stone-ground flour, or rye
flour.
Even though you may not be able to see
the grains in the food, it may still contain
wholegrain fibre if wholegrain components
such as the germ and bran have been
incorporated with the flour.
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Choosing the wholegrain options will help
to increase your wholegrain fibre intake.
For example, if purchasing the following
foods choose the wholegrain options:
Morning tea
— Wholegrain or wholemeal bread
100g tuna (in brine), salad (tomato,
2 leaves of lettuce, 5 slices of
cucumber) and low fat cheese melt +
2g
2 slices of grainy bread
+/- 1 piece of small fresh fruit
6g
3g
— Wholegrain or high fibre breakfast
cereal
— rolled oats or porridge
1 piece of small fresh fruit
3g
Lunch
— Wholegrain crispbreads
— Wholegrain rice cakes
— Brown rice
Dinner
— Wholemeal pasta
200g of lean protein (lean red meat,
fish, chicken or pork)
0g
A High Fibre diet might include:
1 cup of cooked vegetables
5 –8g
Breakfast
1 medium potato (with skin)
Total
3g
35g – 39g
1 bowl of wholegrain cereal
(eg: rolled oats or bran based
cereal)
(*depending on cereal)
+/- 1 piece of small fruit
1 cup of low fat milk
4 –11g*
Seek an Accredited Practising Dietitian for
Individualised Advice.
3g
0g
or
2 eggs (once a week), 2 slices of
wholegrain bread
6g
+/- 1 piece of small fresh fruit and
1 yoghurt (low fat)
3g
1g
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Laxatives
Laxatives are generally divided into four
groups: bulking agents; stool softeners and
lubricants; osmotic agents and stimulant
laxatives. They are available in several
different forms, for example: tablets,
granules, syrups, and enemas. Many
proprietary preparations are a combination
of laxatives from more than one group.
Some laxatives may be better at
preventing constipation rather than treating
established constipation. Often the choice
of laxative will depend on the cause of the
constipation, whether it is acute (short
term) or chronic (long term) constipation,
what other measures are being taken,
whether there are co-existing medical
conditions (such as heart disease, kidney
disease or diabetes), the person’s age
(particularly relevant for infants and the
elderly) and situations such as pregnancy
or breastfeeding.
All laxatives can cause unwanted or
unpleasant side effects. Most commonly
the adverse effects are nausea, abdominal
pain, flatulence, bloating and rectal
irritation. The more serious consequences
of dehydration and electrolyte depletion
have to be considered in some patient
groups. However, when the appropriate
product is chosen and the laxative is used
correctly, problems are unlikely to occur.
Bulking agents
Bulk forming laxatives absorb water to
increase faecal bulk. To ensure laxative
effect they should be taken in conjunction
with adequate fluid.
The common bulking agents are natural
“high fibre” products such as bran, guar
gum, ispaghula, psyllium and sterculia.
Increased fibre in the diet from cereals,
fruit and vegetables can also act as a bulk
14
Page 14
forming laxative.
Some preparations contain stimulant
laxatives such as frangula bark (buckthorn)
or senna granules.
If dietary management of constipation is
not effective, bulk forming laxatives are
normally considered the first choice for
mild or chronic constipation. They may be
less effective in poorly mobile elderly
individuals where initially a stimulant or
combination laxative would be preferred.
The bulking agent/high fibre laxatives
usually begin to work within 24 hours,
however, the full benefit may not be
evident for several days.
Stool softeners
Docusate and poloxamer have a
detergent-like action which is thought to
allow greater penetration of fluid into the
faeces, thereby softening the stool. Liquid
paraffin is a lubricant. These agents are
best used to treat acute constipation and
prevent straining (for instance after rectal
surgery). They have little value as single
agents in the treatment of chronic
constipation. In commercial products
docusate is often combined with stimulant
laxatives (senna or bisacodyl). Stool
softener laxatives may take one to three
days to be effective. The combination
stool softener/stimulant preparations work
more quickly.
The use of liquid paraffin products may
reduce the absorption of fat soluble
vitamins (A, D, E, and K).
Osmotic agents
Glycerol, lactulose, magnesium and
sodium salts, polyethylene glycol, sodium
picosulfate and sorbitol are classified as
osmotic laxatives. All act by holding water
in the intestine by osmotic force.
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Sodium picosulfate also acts as a
stimulant, and the magnesium and sodium
salts (magnesium carbonate, citrate,
hydroxide and suphate, sodium citrate,
phosphate and sulfate) also stimulate
peristalsis.
Glycerol has lubricating properties and
may also act as a stimulant due to local
irritant effects.
Polyethyleneglycol (PEG) is usually
combined with electrolytes to produce socalled iso-osmotic solutions, minimising
water and electrolyte loss. The iso-osmotic
preparations are generally the first choice
to prepare the bowel for diagnostic or
surgical procedures. In constipation it may
take 2 to 3 days to be effective.
The low volume sodium phosphate and
sodium picosulfate laxative preparations
should be used with caution in the elderly
and avoided in the young because of the
risk of dehydration and electrolyte
disturbances.
Lactulose and sorbitol are used for the
treatment of chronic constipation and
opioid induced constipation. The onset of
action for lactulose and sorbitol is one to
three days. The iso-osmotic laxatives and
Page 15
the magnesium and sodium salts act within
one to three hours when taken orally or
within two to thirty minutes when given
rectally.
Stimulant laxatives
Stimulant laxatives are thought to act
directly on the nerve endings in the colon
and thus increase the activity of the bowel
muscles.
The most frequently used stimulants are
bisacodyl, the anthraquinone derivatives
(senna, cascara and frangula bark) and
sodium picosulfate. The anthraquinone
based laxatives may cause discolouration
of the urine.
Stimulant laxatives can be used in the
short term treatment of moderate to severe
constipation and, usually with other
laxatives such as osmotic agents, in
management of chronic constipation or for
bowel preparation.
The time taken for onset of action for
stimulant laxatives taken orally is about six
to twelve hours; when used rectally, about
15 to 60 minutes.
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Some commercially available laxatives:
Stool Softeners and Lubricants:
Bulking Agents:
Active ingredient
Brand name
Active ingredient
Brand name
Docusate
Coloxyl
Guar gum
Benefiber
Poloxamer
Coloxyl drops
Ispaghula
Fybogel
Paraffin liquid
Agarol, Parachoc
Isaghula/psyllium
Agiofibe
Psyllium
Metamucil
Psyllium/maize starch
Nucolox
Sterculia
Normafibe
Osmotic or Iso-osmotic Agents:
Active ingredient
Brand name
Glycerol
Glycerin
suppositories
Lactulose
Actilax,
Duphalac
Sorbitol
Sorbilax
Polyethyleneglycol
Colonlytely,
Glycoprep,
Movicol
Magnesium &
Sodium
Salts
Fleet, Microlax,
PhosphoPrep,
Picolax,
PicoPrep,
Epsom Salts
Stimulant Laxatives :
Active ingredient
Brand name
Bisacodyl
Bisalax, Durolax,
Fleet
suppositories
Senna
Bekunis,
Laxettes,
Nu-Lax, Senokot
Sodium picosulfate
Durolax drops
Combination Products
Bulking Agents and Stimulants:
Stool Softeners and Stimulants :
Active ingredient
Brand name
Active ingredient
Brand name
Ispaghula, Psyllium,
Agiolax
Senna granules
Docusate, bisacodyl
Coloxyl
suppositories
Docusate, senna
Coloxyl with
senna,
Sennesoft
Sterculia, frangula bark Normacol Plus
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Treatment:
examples of useful
laxative combinations
The aim is to change the
form of the motion to a
“sausage”.
Simple Constipation:
Commence with increasing dietary fibre, and
if necessary, add a bulking agent. If the stools
are regular but excessively hard, add a
softening agent such as plain Coloxyl. If
stools are infrequent but not hard, stimulants,
lubricants or osmotic agents are required
for example Durolax, Nu-lax, Agarol or
Sorbitol.
Irritable Bowel
Constipation:
Begin with careful dietary modification.
Bulking agents may be useful but not
always. If the response is inadequate and
pain is a major problem add Colofac. If pain
and severe constipation are not otherwise
responsive try Zelmac. If pain is intermittent
and diarrhoea is prominent try a small dose
of Tricyclic antidepressant such as
Tryptanol 10-30mg daily.
In patients with megacolon, fibre is not
helpful. Bulking agents are rarely helpful.
Megacolon patients must avoid laxatives
with high anthraquinone content. They will
usually require a combination of multiple
laxatives, for example: Plain Coloxyl 120mg
2-4 daily, Nu-lax 1 teaspoon daily and
Durolax tablets 2-3 tablets second or third
daily. If the response is still inadequate try
adding one or more of Movicol, Epsom
salts or Sorbilax.
Laxatives with high
anthraquinone content:
— Cascara Preparations
— Ford Pills
— Peritone
— Senna preparations
— Herbal teas for constipation
Slow Transit
Constipation:
In patients with normal colon length
increase dietary fibre and add a bulking
agent. If the response is inadequate add
Sorbitol. If the response is still inadequate
add stimulants such as Durolax or Nu-Lax .
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Treatment of pain
associated with
constipation especially
IBS:
The use of antispasmodics such as
Mebeverine (Colofac) is beneficial to a
significant number of patients, although
their use sometimes worsens the
constipation.
They should be used in conjunction with
an increase in dietary fibre and/or bulking
agents to achieve a change in stool form
initially or concurrently. Low dose tricyclics
such as Amitriptyline (10mg at night) are
effective in many patients in terms of pain
control.
There is a belief that the use of Zelmac,
early rather than later, in treatment is
helpful particularly in IBS-C. This is useful
in both males and females across a wide
age range and can be used long term if
there is a beneficial outcome.
Probiotics
Probiotics are defined as live
microorganisms which when administered
in adequate amounts confer a health
benefit to the host. These probiotic
microbes are contained in various
fermented food products that have been
eaten for centuries. Kefir is a fermented
milk drink which contains a variable
mixture of bacteria and yeast, commonly
consumed in Russia and the Middle East
for thousands of years. There are now an
increasing number of lactobacilli and
acidophilus strains with probiotic claims.
Many of these pass through the gut after
eating but most do not colonise or persist
in the colon because the existing bacterial
population fiercely defend their territory.
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Page 18
Probiotics may have a role in restoring the
bacterial population following antibiotic
therapy or diarrhoea. An increasing number
are being shown, at least in the laboratory,
to have a beneficial effect on the immune
function of the gut, the unconscious
nervous system controlling gut muscular
activity and sensitivity and perhaps an
effect on other bacteria present. Currently
there are more claims for their benefit than
evidence to that effect though it remains
distinctly possible that probiotics will have
a future beneficial role in gut disorders
including constipation and bloating.
Myths
and Facts:
1. Does constipation lead to toxins
being released into my body?
It is a myth that the colon is like a stagnant
drain, being only responsible for reabsorption of water. It is, in fact, an
extraordinarily dynamic environment with a
large variety of activities occurring night
and day. It is filled with 1 to 2 kg of
bacteria comprising 400 different species.
True multiculturalism! These are the
backbone of the process of fermentation,
reducing fibre and resistant starch to short
chain fatty acids including butyric acid
which has a major role in nourishing the
cells lining the colon and preventing
disease. The energy produced by this
process, stimulates further bacterial growth
and consequently a larger stool.
The concept that the colon produces
toxins is a total myth. Infrequent bowel
motions do not lead to disease. Blaming
constipation for tiredness, lack of energy,
fatigue, muscle weakness, allergies, poor
sleep patterns, depression and a myriad of
other complaints are simply untrue.
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Colonic irrigation often promoted as a
“cure” for these symptoms is exploitation
by often charismatic practitioners. The idea
that colonic irrigation can prevent any ill
effects is misconceived particularly as the
irrigation only empties the left side of the
colon and is not without risk of perforation
of the bowel.
2. Does a long colon cause
constipation and should it be
shortened?
Surgery to shorten the colon has no place
in the treatment of simple constipation
regardless of the bowel length.
3. Do my hormones cause
constipation?
Lower abdominal pain can be caused by
both gynecological and bowel disorders. It
is very important to distinguish between
the two by careful history and examination.
Irritable bowel symptoms are frequently
attributed to gynecological causes; this
can lead to unnecessary and at times
counter productive surgery. Many women
notice that the level of constipation varies
with the phase of the menstrual cycle; in
general, higher levels of progesterone are
more likely to be associated with
constipation.
There is absolutely no role for any of the
other gastrointestinal hormones except for
perhaps a connection with the brain-gut
axis where stress, anxiety and depression
can provoke changes in bowel function, for
example nervous diarrhoea.
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4. Is constipation due to a diet
poor in fibre and is it best
treated by dietary fibre?
It is firstly important that individuals
understand the sources of fibre and how to
develop a high fibre diet. Community
programs in the past which have
emphasized the importance of fibre,
particularly in the form of cereal fibre have
resulted in an improvement of constipation
and halving of laxative use. There is good
evidence that the average intake of dietary
fibre is only a little more than half the
recommended intake largely due to
misconceptions about fibre sources. For
example the concept that salads are a
great source is a myth.
It is important to start slowly with
increasing the fibre content of the diet as
many people find a high fibre intake
causes bloating. Gradual increase in fibre
allows adjustment to occur. Wheat in the
form of bread and pasta is a major source
of fibre and if bloating develops
consequent upon fermentation in the colon
then wheat intolerance is blamed. This
emphasizes the need for fibre to come
from a large variety of sources including
cereals, fruit, and vegetables.
The constipation seen in nursing homes
may well be due to dietary fibre deficiency.
A bulking agent can be of considerable
value.
Individuals with slow transit constipation
may find it particularly difficult to eat a high
fibre diet and in such individuals fibre will
not result in improvement in their
constipation.
There are of course other hormones that
do disturb bowel function. An overactive
thyroid can be associated with diarrhoea
and an under active thyroid with
constipation. Elevation of calcium levels in
the blood may also cause constipation.
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5. Will drinking a lot more fluid help
my constipation?
7. Is Chronic use of Laxatives
unhealthy?
This notion needs to be viewed with some
understanding of the fluid exchanges in the
gut. Overall, approximately 10 litres of fluid
will enter the beginning of the small
intestine. This comprises 2 litres from the
diet, 2 litres from gastric juice, a further 4-5
litres from the liver, biliary system and
pancreas and secretions from the small
intestine. This volume of liquid is reduced
to 1.5 litres by the time that it reaches the
caecum. It is further reduced to 100200mL in the stool.
7a Does Chronic Laxative damage the
nerves in my bowel?
Experiments increasing fluid intake have
shown no influence on bowel habit.
Drinking an additional 2 litres will do
nothing to overcome constipation.
The concept that tea and coffee can be
constipating because of dehydration is
false. Both contain caffeine which is a
stimulant to the gut and might promote a
bowel action.
6. Will exercise help my
constipation?
It is well recognized that being confined to
bed at home or in hospital results in
constipation. The extension to the idea that
moderate physical activity may help
individuals with mild constipation has not
been supported by any clinical evidence.
Early morning physical activity may
augment the increase in colonic muscular
contractions that occur upon waking. A
fibre rich breakfast takes advantage of the
increase in bowel activity.
There are however many other benefits of
moderate physical activity particular in
terms of cardiovascular health.
20
There is no evidence that stimulant
laxatives taken at the recommended dose
are harmful to the colon. While the
development of ‘Melanosis Coli”, an easily
visible brownish black discoloration of the
colon, occurs with anthraquinone use, this
pigmentation is unassociated with any
neuronal change. No scientific study has
been able to show that stimulant laxatives
taken in recommended doses can cause
damage to the normal colon. Patients with
true Megacolon may have toxic effects
from anthraquinone containing laxatives.
A small group, where laxative abuse is
common (particularly young females with
eating disorders and those obese people
mistakenly attempting to lose weight with
laxative over usage) may damage nerves in
the bowel.
It is important therefore, to reassure
individual patients that laxative use, carried
out with medical advice regarding diet, is
safe.
7b Does chronic use of laxatives
increase the risk of colorectal or
other cancers?
The answer NO.
Colorectal cancer is the commonest
internal cancer in the community affecting
slightly more men than women. In Australia
there will be more than 12,000 new cases
per year, amounting to 30 patients per day,
12 of whom will die; a mortality of 1 death
every 2 hours. It is the commonest cause
of death in non-smokers and the only
potentially preventable cancer in men and
one of two, the other being cervical, in
women.
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Bowel cancers develop over 5 to 10 years
from small adenomas or polyps. There is
no evidence that laxative use is a factor
promoting polyp growth.
Colorectal cancer is not more common in
people with constipation. Colon cancer risk
begins at the age of 40 and doubles in
each decade thereafter. As younger
women may be the major consumers of
laxatives this is not reflected in the
prevalence of colorectal cancer.
7c Can Laxative intake cause a
chemical imbalance in my blood?
Laxative abuse may result in low serum
potassium, though usage at the
recommended dose has not been shown
to have any demonstrable change in serum
electrolyte levels.
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7e Do Laxatives cause addiction?
Many individuals are dependent on laxative
use to produce a regular bowel motion.
This dependency is particularly prevalent
when laxatives are misused for weight
control or eating disorders. If chronic
constipation has been diagnosed and
understood by the individual and their
doctor, then laxative use may need to be
lifelong. Under such circumstances
patients should be reassured that there are
no long term consequences of laxative use
provided this is done together with medical
advice. A balance needs to be struck
between the benefits of laxative use in
terms of physical wellbeing against the
background of myths regarding potential
harm.
7d If I start taking laxatives will I have
to keep increasing the dose
(tolerance)?
Tolerance to stimulant laxatives may occur
in the most severe patient group with slow
transit where other laxatives are ineffective.
Tolerance seems to be uncommon in the
majority of users and needs to be
separated from the natural history of
constipation which may slowly worsen over
time. Nevertheless there are anecdotal
reports of changing laxatives being
beneficial after some months usage and
provided the patient understands why
laxatives have been recommended, that
practice is not harmful.
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Fibre
Fallacies
Myth
Fact
Fibre equals
unprocessed bran
Fibre is much more than bran. There are many different
types of dietary fibre; wheat bran does not contain them all.
If some bran is good,
more must be better
Large amounts of wheat bran are undesirable for several
reasons. These include the presence of phytic acid which
can bind minerals and also the chance of taking in large
quantities of pesticide residues if bran is eaten by the cupful
rather than the tablespoon. 2 tablespoons per day is wise,
more is not.
Eating fibre is a
good way to lose weight.
Foods high in fibre are usually low in fat and fit well into a
weight reduction program. However, eating large quantities
of dietary fibre or taking laxatives to lose weight is useless
for loss of body fat and potentially harmful.
It is recognized that foods which are lower in Glycaemic
Index (GI) * and Glycaemic Load (GL) ** (usually rich in grains
and fibre) assist in weight loss. Choosing grainy cereals and
cereal products in controlled portions are essential for
stabilizing glucose levels and weight.
Fibre equals roughage
The idea that fibre enters one end of the gastrointestinal
tract and emerges from the other is simplistic and incorrect.
Some types of fibre are 100% fermented and work by
increasing colonic bacteria which then add to faecal bulk.
Salads are a good
source of fibre
Salad vegetables are good sources of vitamins but most are
not high in dietary fibre. Peas, beans, broccoli, corn and
spinach are better sources of fibre than celery, cucumber
and lettuce.
Fibre is visible
Not always. Wholegrain fibres can often be seen but soluble
fibres such as pectin and gums have no obvious fibrous
appearance.
* The Glycaemic Index (GI) is a way of comparing the effect of different carbohydrate foods on the levels of glucose
(a sugar) in our blood. Low GI foods raise blood glucose levels gradually and provide a steady energy source for
the body. High GI raise blood glucose levels quickly, providing a quicker source of energy.
** The amount of carbohydrate together with the rate of release is known as the Glycaemic load (GL). GL is also
important to determine the total impact on glucose levels.
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Important questions
about Constipation
How long has constipation
been present?
Long duration and under 40 years of age – check dietary
fibre intake.
Over 40 years of age, particularly if constipation is recent, or
if dietary or life-style changes fail, make sure colon cancer is
excluded.
Do you eat enough fibre?
What do you eat
for breakfast, lunch
and dinner?
You should eat at least 30g of fibre per day; check your fibre
intake with a fibre counter. You may also need a bulking
supplement.
Do you have pain on
passing a motion?
This could be due to a fissure or complicated haemorrhoids
Have you had any bleeding
from the bowel?
Consider colon cancer, if over 40 years of age
Do you have a family
history of colon polyps
or cancer?
If yes, a colonoscopy from age 40 is vital
Discuss their possible relationship with your doctor
What medications are you
taking? Laxatives, opioids,
antidepressants, analgesics,
aluminium containing
antacids, iron supplements,
some heart and blood
pressure medication.
Travel
Tips:
Food on airlines and in hotels often lacks dietary fibre. Try to find a high-fibre cereal or
take your own. Fruit is usually available and wholegrain breads are becoming more
common. When eating out, ask for extra vegetables or consider vegetarian dishes as an
entrée or main course.
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Appendix 1
The process of
digestion:
LIVER
SPLEEN
STOMACH
GALL BLADDER
DUODENUM
PANCREAS
SMALL INTESTINE
COLON
Jejunum
lleum
APPENDIX
RECTUM
Digestion is the process
of breaking food into
small components that
can be absorbed by the
intestine.
It occurs in the digestive system which
works day and night to churn, soften and
squeeze food, using digestive juices to
24
break down food and release its nutrient
components to provide the body with
energy, essential vitamins, minerals,
proteins and fatty acids.
The process of digestion starts in the
mouth when an enzyme present in the
saliva begins the digestion of
carbohydrate. In the stomach, the gastric
cells produce hydrochloric acid and
enzymes which begin digesting proteins.
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The stomach acts as a reservoir, releasing
small amounts of food into the small
intestine. Most digestion occurs in the
duodenum under the action of pancreatic
juice containing enzymes, and bile from the
gall bladder. Enzymes break down proteins;
fats are converted to fatty acids; and
carbohydrates to disaccharides and
monosaccharides. Most nutrients are
absorbed from the duodenum and jejunum
but vitamin B12 and bile acids are
selectively absorbed from the ileum.
Dietary fibre and some starches escape the
enzymes in the small intestine and enter the
large bowel where bacteria breakdown all
the soluble fibre and resistant starch, and
some insoluble fibre.
Approximately 9 litres of fluid enters the
jejunum each day. This includes five litres
from foods, drinks, saliva and gastric juice
plus four litres of bile, pancreatic juice and
secretions from the small intestine.
Within the jejunum, 4 – 5 litres of the fluid is
reabsorbed and another 3-4 litres is
absorbed in the ileum. Approximately 1.5
litres enters the caecum through the ileocaecal valve each day. The colon then plays
a major part in fluid reabsorption and faecal
volume is only 100-200mL a day.
The large intestine consists of the colon
and rectum and is a muscular tube about
two metres long. Its main function is to
absorb water and allow fibre to be broken
down by bacteria. This produces valuable
fatty acids that feed the cells in the colon. It
is also normal for this process to generate
gas, which may trouble some people.
The rate of movement of the residue is
determined by muscular action. If there is
too much action, diarrhoea occurs – if there
is too little, constipation results. Normally
the movement of the colon is well
coordinated, but it is a complex system and
if the rhythm is disturbed, pain and
alterations in bowel habit can occur.
Page 25
The rectum at the lower end of the large
intestine is normally empty but regularly fills
up to produce the urge to defaecate. The
muscular action in the anal canal, which is
connected to the rectum, prevents the
involuntary passing of faeces, but can relax
long enough to allow wind to escape.
What happens in the
colon?
Within the large bowel or colon, bacteria
ferment fibre, mucus and resistant starch.
During this process:
— the bacteria grow and multiply
— gases such as carbon dioxide,
hydrogen and methane are produced
and
— volatile fatty acids (acetic, propionic
and butyric acid are generated)
Flatus:
The major gases produced include:
Nitrogen – swallowed from air. Most is
reabsorbed in the stomach and small
intestine, but about one third of the total
volume of gas in the colon that is
unidentified is probably nitrogen.
Oxygen – also swallowed and almost
totally reabsorbed in the stomach and
duodenum, causing anaerobic (without
oxygen) conditions in the small intestine
and colon.
Carbon Dioxide – produced from the
interaction between gastric hydrochloride
acid, dietary fatty acids and bicarbonate
from the duodenum and pancreas is
present in the small intestine. The
interaction of fermentable material and
organic acids with bacteria in the colon also
produces carbon dioxide in the colon.
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Hydrogen - produced throughout the
colon as bacteria ferment fibre, resistant
starch and any unabsorbed sugars (lactose
or sucrose) or sugar alcohols such as
sorbitol. As with all gases present in the
colon, some hydrogen is reabsorbed from
the colon and expired from the lungs. The
remainder is used by bacteria in the colon
or passed as flatus. The amount of
hydrogen expired from the lungs can be
measured in a breath hydrogen test to
assess absorption of sugars.
Methane – made by methane-producing
bacteria, commonly present in the left
colon. These bacteria reduce carbon
Page 26
dioxide and hydrogen to methane,
consuming five parts of gas (four hydrogen
and one carbon dioxide) in the process.
Not everyone produces methane. In theory,
those who do should have less flatulence
than those who do not. Methane can also
be measured in the breath.
Hydrogen Sulphide – produced by some
bacteria that change sulphate to sulphide,
It is the major cause of smelly gas.
Acetate – produced by bacteria from
carbon dioxide and hydrogen. It is also
generated when bacteria ferment soluble
fibre and resistant starch.
Appendix 2
Features and
Investigations:
Incidence
Gender incidence
Investigations*
Simple
Constipation
Commonest
Female>Male
• Nil
Irritable Bowel
Syndrome with
constipation
Common
Female>Male
• Nil
• Colonic Transit Study
• enteric sensitivity
Slow Transit
Constipation
Uncommon
Female>>Male
• Colonic Transit Study
• Balloon expulsion test
• +/- Anorectal
manometry
Defaecation
Disorders
Uncommon
Female>>Male
• Balloon expulsion test
• Anorectal manometry
• +/- Colonic Transit
Study
* Have there been any indications for colonoscopy?
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Notes
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