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Taming the stubborn bowel; a constipated person’s guide to defaecation.


colonThe colon is an obstinate beast.  It likes to have its own way and will not work to your order.  The more you try to bend it to your will, the more it will resist.  It is the ‘awkward’ organ.   It demands attention as soon as you wake up and if you don’t allow it the time it needs, it will get you an hour later when you are sitting on a crowded train, then give up and leave you uncomfortable and frustrated for the rest of the day.

It has its own routine, which may not always conform to yours.  So if you fly away to New York for a few days, it will stubbornly continue to wake you up in the early hours.

And so, you try to coax it into submission with bran or oats, or a drink or two of prune or beetroot juice.  Turning desperate, you force it to submit to Senna or Laxedo or try that new tablet that turns your bowels to water, but it just complains with pain and bloating and – the shame of it – may even leak and stain your clothing with foul smelling liquid.  If you insist on showing it who is in charge, you will have a battle on your hands.

So try to understand your recalcitrant colon.  Let me take a few minutes to explain how I think it works.


Now the science.

Most people are fortunate enough to take it for granted but in reality, defaecation is quite a complicated business involving the integration of conscious and unconscious physiological mechanisms mediating colonic propulsion, rectal filling and evacuation of faeces.

There is a prominent diurnal rhythm of colonic activity.  For most of the day an throughout the night, the colon receives meal residues from the small intestine and mixes these with the trillion or so  bacteria that live in the colon, allowing unabsorbed nutrients to be fermented and salvaged and leaving a semi solid plug or indigestible fibre and bacteria.  Overnight the colon fills with more material.  Then upon waking up or shortly after, the colon undergoes a more propulsive form of contractile activity.  Powerful persistaltic waves sweep down the distal descending part of the colon  propelling faeces, like a pig through a python, into the rectum.  The rectum functions as a reservoir or container, retaining the faeces until the time is appropriate to release them.  The arrival of colonic content stretches the wall of rectum like a balloon, stimulating sensors that increase the tone of the rectum relax the inner ring of the anal sphincter and trigger a strong conscious urge to defaecate.

But we are a territorial species.  We can’t just let the colon do its thing, drop our load, and walk on like cows or sheep.  We control when and where we deposit our faeces.   Our defaecation is orchestrated a loose association of neurones in the brain stem, sometimes called the defaecation centre, but also involves an important relay and reflex centre in the low spinal cord.

Surrounding the internal anal sphincter is another ring of muscle, the external anal sphincter, which is under conscious control and prevents inadvertent defaecation until the time and place are right.  If conditions are not appropriate, the external sphincter and the puborectalis of muscle linked to it, contract tightening the sphincter and pulling the anorectal junction forwards to create an acute angle which blocks passage of a solid stool in much the same way as a sharp bend on a narrow road stops a coach getting round.  These actions will preserve continence when the rectum is distended by the arrival of a new load of faeces  and also when the abdominal pressure increases during walking, talking, laughing, coughing or getting up from a chair.  But if the situation is appropriate, the external sphincter and puborectalis will relax and with a little abdominal push, the rectum will do its thing.


Training the colon.

If you are constipated these processes do not operate smoothly.  Colonic propulsion may be impaired so that insufficient faeces arrive in the rectum to trigger an urge to defaecate (colonic inertia).  There may be a reduction in rectal sensitivity.  Straining too hard may cause the external sphincter and puborectalis to contract blocking defaecation (anismus).

It is so important to relax and allow the time for the colon to work properly. The colon is stubborn because it is sensitive. We are rarely so vulnerable as during defaecation*.   If we feel pressurised, anxious and in unfamiliar surroundings, our colon will shut up shop and stop working. So give it the time it needs.  Do not try to make it go until it tells you it needs to.  The colon does not like to be hurried.

Extend your morning routine.  Make sure you have a go to bed early and have a good night’s rest, set your alarm to ensure enough time to attend to its needs in private.  Have a cup or two of warm tea and read in bed reading before getting up.  Ten minutes exercise or yoga can also encourage the colon to move.  I find that a run in the park and a cold swim does wonders for the bowels. Others find a cigarette works just as well.  I do, of course,  realise that some of you may live in quite crowded accommodation and responsibilities to get your family up and going may not allow you the luxury of relaxed defaecation; that may explain why you are constipated. But do try to find that time and space.  You will feel much better.

Then when you feel the urge to go, settle yourself, breathe deeply and try to let nature take its  course.  Some bowel ‘experts’ will tell you to sit on the loo with your feet on a (wooden or plastic) stool to open up the ano-rectal angle, but relaxation does that more effectively by loosening the tension in the pubo-rectalis sling of muscle.  I personally recommend the UCH abdominal brace.  Sit up straight with your hands on your hips, breathe deeply with a long expiration.  Breathing out in this way increases the activity in the parasympathetic nervous system which encourages colonic peristalsis, driving mass movements and rectal filling.  If your colon needs a bit of extra coaxing – and this isn’t for everyone -, you could try lubricating your little finger with KY gel and gently stimulating your anal canal.  This excites the anocolonic reflex which promotes peristalsis.     

You may wish to encourage your colon by consuming a diet that contains sufficient fruit, vegetables and cereal fibre to bulk up colonic contents and stimulate peristalsis. Don’t be too put off by the requirements of a low FODMAP diet.  Food intolerance does not require an  exclusion diet and there are plenty of alternatives to high FODMAP foods.

If something has happened to make you anxious or frustrated and trapped and your bowel has responded in kind, try to talk to somebody about your situation.  Consider getting help from a counsellor or therapist.  Make sure you get enough rest and space for yourself.  Remember a relaxed and confident bowel is more likely to work well.

And if nothing works and you have to take laxatives, try bulking agents such as Fybogel first before going on to stimulant or irritant laxatives, but continue to try to make adjustments to your life style and situation to encourage a more natural bowel action so that in time you can dispense with the drugs.

Whatever you do, be patient.  Your colon won’t be rushed.  It moves slowly and will only change if it feels safe enough to do so.  So make the changes necessary to get it going, keep on with them and wait for it to respond before making further adjustments.

Above all, treat your bowel well.  Give it the time and the space it needs and it will treat you well too.


  • Reputedly, the most constipated mammal is the Three-toed Sloth.  Living in the jungles of Central and South America, this strange creature spends nearly all its time hanging upside down high up in the trees, only descending in order to defaecate when it is very vulnerable to a marauding jaguar.  It is perhaps not surprising that it only defaecates once a week (type 1 on the Bristol stool chart) .


3 comments on “Taming the stubborn bowel; a constipated person’s guide to defaecation.

  1. Rick
    October 15, 2018

    Loved it. Thanks.


  2. Babs Halfpenny
    October 29, 2020

    Made me smile, but have taken it on board, patience may be a virtue but I don’t have it, so must learn it. Thanks for the article.


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This entry was posted on November 2, 2016 by in Constipation, defaecation, Uncategorized and tagged , .

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