• Irritable Bowel
• About IBS
• Tests and lifestyle
• Sub-groups of IBS
• Bloating
• Other features
• Symptoms NOT IBS

The pain from IBS arises from the colon - either distension or spasm but the colon appears normal at colonoscopy


IBS has no obvious pathology but should not be dismissed as a minor conditon. The symptoms can be very disabling


Cramping discomfort or pain in the lower abdominal often prior to a bowel motion is a major part of IBS

What are the common symptoms?

• The diagnosis of irritable bowel syndrome (IBS) relies primarily on the recognizing a pattern of symptoms - similar to the diagnosis of migraine headaches.
  
  • Alternating diarrhoea / constipation is the key symptom.
    
    • It is common to describe several days (3-4 days) of constipation followed by 1-2 days of loose bowel motions.
    • It is common to pass several bowel motions in the morning – the first may be before breakfast (immediately after awakening). Subsequent bowel motions may be only 20-30mins apart and are usually looser each time.
    • Urgency - rushing to the toilet - is common.
    • There is often a sensation of incomplete emptying - "a feeling of something still to pass".
  • Abdominal pain
    
    • This is usually in the lower abdomen.
    • Cramping (or griping) in nature - "bent over".
    • Usually there is some increase in pain prior to a bowel motion and some relief after a bowel motion.
    • However the pain can persist for several hours and be unrelated to a bowel motion.
  • Symptoms for several years makes IBS a more likely diagnosis
    
    • Symptoms usually start in 20's or 30's but can begin at any age (see below - background information).
    • The severity of symptoms can vary a lot - often related to stressful life events.
  • Irritable bowel syndrome commonly follows a gastroenteritis illness
    
    • About ¼ of people with IBS can link the onset of symptoms to an episode of gastroenteritis(or food poisoning).
    • Frequently the type of gastroenteritis is not identified.
    • However a history of sudden onset of vomiting and diarrhoea lasting or a few days makes the diagnosis of gastroenteritis very likely.
    • In this setting symptoms of IBS usually gradually resolve over 1- 2 years.
    • There may be frequent relapses that can "suggest" more episodes of gastroenteritis but this is simply part of the IBS response to the initial infection.
    • There is no way of speeding up this process of gradual resolution but I often recommend a course of antibiotic (tinidazole for 1 week).
    • It is a frequent observation that new food intolerances develop after the gastroenteritis illness - e.g to milk, bread, fruit, coffee etc.
    • A proportion of people do have persisting symptoms of IBS.


• Abdominal bloating is often part of irritable bowel syndrome but can also be the sole presenting complaint.
  
  • Clothing may feel uncomfortable; the swelling usually increases towards the evening (see subtypes).
  • There is often increased abdominal gurgling and rumbling.
  • Nausea and anorexia may occur particularly in the early morning – commonly better by mid-morning.
    

Some other symptoms are associated with irritable bowel syndrome.

• These symptoms have an association with IBS but the reasons for this are not known.
  
  • Tiredness.  This is the commonest associated symptom - up to 3/4 of people with IBS report this symptom!  The reason for this association is unclear.  There is an association with chronic fatigue syndrome
    
  • Painful periods. Pain with sexual intercourse.
  • Bladder symptoms.  Urinary frequency, a sensation of incomplete bladder emptying.
  • Lower back pain.  Sometimes this discomfort comes from the colon but usually it is simply as associated symptom.
  • Fibromyalgia.  Diffuse muscle aches (sometimes with  “trigger points”). Treatment with amitriptyline can help this symptom and also help IBS symptoms.
    

There is a close and complex interaction betwen the gut and the brain


Nerves in the gut

Background information

• Irritable bowel symptoms are common.
  • Community studies suggest a prevalence of 15-20% across all ages.
  • IBS is more common in women than in men.
  • IBS commonly starts between 15 and 35 years.
  • A family history is common
    • There may be a genetic link.
    • Some families may be more open to discussing IBS symptoms therefore the family history is known.
      
• Symptoms that start after 35 years may be due to IBS,
  • but it is very important that a colonoscopy is performed to exclude any important diagnosis.
    
• Onset after the age of 35 may be due to precipitating causes such as;
  • Gastroenteritis illness.
  • Major dietary changes.
  • Medications such as antibiotics.
  • Cholecysytectomy (removal of the gallbladder).
  • Major stressful life events.
    
• IBS tends to persist over a lifetime.
  • There is a lot of variability and often long periods of time when there are minimal or no problems.
  • A diagnosis of IBS rarely changes. That is it does not develop into any other bowel problems. Diagnosis by a specialist and a colonoscopy test will give a very "secure" diagnosis.
  • There is no association with depression or anxiety but these problems will aggravate IBS.
    
• IBS can be subtyped into;
  • Diarrhoea-predominant.
  • Constipation predominant.
  • Alternating IBS.
  • Post-gastroenteritis irritable bowel could be considered to be another subtype.
    
• This subtyping is only of modest use as people can change from one subtype to another.
  • They are useful categories for a discussion of treatment options (see subtypes).

What is the cause of the IBS symptoms?

• It is a combination of
  • Abnormal motor (muscular) activity of small intestine and colon.
  • And abnormal sensitivity.
    
• Some symptoms can be explained as an exaggeration of normal physiological reflexes.
  • There is more rapid passage of food through the bowel with mental and physical stress.
  • It is common to induce contractions of the colon (causing cramping) after meals – particular a larger meal or a fatty meal.
    • Normally this reflex is responsible for 1-2 bowel motions per day but can be more frequent in IBS.
      
• Abnormal sensitivity
  • This can be termed visceral hypersensitivity.
    • This is partly an abnormal awareness of normal events in the bowel.
  • There is a heightened awareness of colonic distension.
  • Even a normal amount of gas in the colon produces cramping abdominal discomfort.
    
• There are many misconceptions about IBS.
  • It is not due to food allergy 
    • but food intolerances are often important.
  • It is not “ all in the mind”
    • but stress is an important aggravating factor.
  • It is not an infection
    • although an episode of gastroenteritis in the past may have triggered the condition.
  • It is not an inflammation of the bowel
    • IBS is distinct from IBD (inflammatory bowel disease).
  • It does not lead to more serious bowel diseases
    • there is no association with colon cancer.
  • It is not the same as diverticular disease
    • although both problems may co-exist.
    • it can be hard to distinguish the effects of each condition.

Investigations

• This should include simple blood tests .
  • A full blood count.
  • ESR (a test for inflammation).
  • Liver enzyme tests.
  • Tests to exclude  coeliac disease.
  • Studies to check for problems with iron, folate and B12.


• It is recommended that a colonoscopy is required for people over 35 years and is helpful at any age to clarify the diagnosis and relieve any anxiety.


• The more recent the change in bowel habit the more important it is to check the colon.


• There does seem to be a beneficial effect of colonoscopy on symptoms.
  
  • This may simply be a relief of anxieties regarding the diagnosis.
  • It may also be due to a beneficial effect of the bowel washout required for the procedure.
  • A colonoscopy will be normal if the diagnosis is irritable bowel syndrome.
  • Biopsies may be taken of the lining of the bowel – in IBS there are no abnormalities on biopsy.

Management

• Key aspects are an accurate diagnosis,  reassurance that there is no underlying disease and an adequate explanation of the symptoms.
  
• There can be a "cycle of anxiety".
  • Mild bowel symptoms of “uncertain nature ? something important” - leads to anxiety which increases the bowel symptoms.
  • This in turn leads to heightened concerns about the reason for the symptoms.
  • A normal colonoscopy can be very helpful way of "breaking" this cycle.
    
• There is no cure for IBS but significant improvements can be made by following a few simple rules.
  
• Diet and lifestyle changes
  • Diet is discussed fully in the exclusion diet section.
  • The pattern of eating can be as important as the individual food items.<
    • Irregular meals, rushed meals, frequent takeaways or commercial pre-cooked meals are aggravating factors.
  • Breakfast is a key meal.
    • The gut is ready to digest food well after the overnight fast.
  • Missing breakfast, having lunch on the run then having a large evening meal late at night is a common eating habit in our busy lives.
  • Regular unhurried meals, using fresh ingredients, not takeaways or convenience foods, is important.
    • Pizza and coke is not a great meal if you have IBS!!
  • Sudden dietary changes, perhaps according to the latest theories of weight loss or healthy living, can aggravate symptoms.
  • Over-eating or binge eating may "over-whelm" the small bowel with spill-over into the colon.
    • This could lead to fermentation of non-digested food.
  • Some people have found that protein supplements as part of muscle building (whey-based products) aggravate bowel symptoms.
    
• Natural and alternative treatments - these are discussed in depth in another section.
  • In general the key intervention is dietary and lifestyle change.
  • The role of alternative treatments is modest.
  • A brief search on the internet will reveal of myriad of options!!
    • This usually implies there no single highly effective treatment.
      
• There is an association of IBS with heartburn.
  • Both problems can be considered disorders of the motor control of the gut.
  • Similar foods aggravate both conditions.
    • Fatty foods, over-eating and weight gain aggravate both conditions.
  • Treatment of heartburn can help abdominal discomfort and bowel symptoms including abdominal bloating (as well as treating the reflux).
    • There are many potential explanations but the message is that it is worth a trial of medication such as Losec or Somac.
    • Mylanta II contains simethicone which may help bloating as well as temporary relief of heartburn.

IBS can be divided into subgroups

Diarrhoea-predominant IBS

• Avoid the following foods;
  
  • Coffee completely (including decaffeinated coffee).
  • All forms of alcohol (wine may be worse).
  • Spicy foods (chillis).
  • Pure fruit juices (particularly citrus juices).
  • Diet products – artificial sweeteners, soft drinks (including home made soft drinks).


• Drugs that decrease the motor activity (motility) of the gut can be helpful.
  
  • Loperamide is the best.
    • This is commonly used short-term for diarrhoea but is very effective as regular treatment – 1-2 capsules per day.
    • This can be taken as a single morning dose.
    • This is safe for long-term treatment.
    • However it is common for low doses of loperamide to cause a swing over to constipation.
    • In a sense this is reassuring as it shows that there is not any other underlying cause of diarrhoea.
    • The “trick” is to titrate carefully to work out a dose that helps the diarrhoea without causing constipation.
  • Fibre supplements have no value if diarrhoea is the predominant symptom
  • Antispasmodic drugs
    • can be used in addition to loperamide to will reduce diarrhoea and urgency
    • the best option is Colofac taken up to three times daily - lower doses may be effective (Colofac is no longer funded; alternative medication is Merbentyl or Buscopan ).
    • about 1/3 rd of people experience side-effects that limit the usefulness of antispasmodics
    • usually this is “dizziness” or “feeling of fuzziness in the head”.
  • Tricyclic antidepressants at low dose (e.g amitryptyline 10-25mg nocte) may be helpful. They mostly help because of a pain modulation effect.  There is also the effect of slowing bowel transit.
  • Alosetron was developed for diarrhoea-predominant IBS in females was withdrawn after cases of ischaemic colitis were described in association with use of this drug  - this is a rare but significant complication.  Limited use on a restricted programe continues in the USA but there are no plans for introducing this drug in NZ.  This is a disappointing outcome for a very promising new drug  
    

Constipation-predominant IBS

• Sometimes the problem is actually “pure” constipation rather than IBS.


• Consider dietary and natural treatments for constipation.
  • Kiwi Crush, Aloe Vera juice, Slippery Elm - discussed fully in constipation section.


• Laxatives are useful if prominent constipation.
  • PEG solutions do not aggravate bloating.
  • This is available as Movicol sachets.


• The newer antidepressants have a role (SSRI’s – Aropax, Ciprimal).
  • In contrast to drugs such as Amitriptyline they actually improve bowel habit by increasing gut motility.
  • They also have an effect in reducing abdominal pain.
  • Any additional improvement in a feeling of wellbeing and elevated mood can’t be a bad thing.


• Stimulant laxatives (such as Sennokot, Coloxyl with Senna, Dulcolax) usually cause unacceptable cramping abdominal pain and should be avoided.


• Suppositories should also be avoided.
  • Gentle oral laxatives are the best option to encourage a more regular bowel habit and reduce abdominal pain.


• Tegaserod (Zelmac) is a new medication that has proven benefit in IBS with constipation and prominent bloating.
  • There have been several large studies that clearly show a benefit.
  • The problem is the cost.
  • This medication has recently been withdrawn because of safety concerns (April 2007).
    

Prominent abdominal pain

• The pain of IBS can be the major symptom.


• Low dose amitriptyline (10 -20 mg) taken at night is very effective.
  • This is an anti-depressant medication but at low doses the effect has nothing to do with treating depression.
  • The medication works as a "pain modulator".
  • It seems to decrease “unpleasant traffic” in nerves carrying visceral sensations from the bdomen to the brain.
  • In medical terms – it inhibits afferent pathways.
  • Anti-spasmodics such as Colofac or Buscupan can be tried but have some side-effects - less effective than amitriptyline.
    
• The SSRI type of anti-depressants may have a similar effect and have the advantage of not increasing problems with constipation.
  • I usually use Ciprimal (citalopram).
  • Aropax (paroxetine) has an advantage if there are problems with anxiety or panic attacks.
  • I usually start at half the usual dose recommended for treating depression (1/2 tab at night).

• Typically the abdomen feels comfortable and looks flat in the morning then there is gradually increasing distension during the day.  There may or may not be increasing bloating after meals.


• Studies have shown that the amount of gas in the abdomen is increased but only to a modest degree.
  • There seems to be a cyclical (daily) pattern of relaxation of abdominal muscles and a relaxation in the muscular tone of the bowel allowing the abdominal contents including gas to fill a larger space.
  • Sometimes the distension is dramatic and is described as feeling like “I am 6 months pregnant”.
    
• The symptoms are difficult to treat.
  • Some investigation is required – usually an abdominal ultrasound and sometimes a colonoscopy.  Reassurance of normality is helpful.
  • Diet to reduce wind formation has some effect.
  • Exercises to increase tone in abdominal muscles are helpful and weight loss to counteract the trend to central obesity is also important.
  • Constipation may have a contribution to the symptoms.

Gynaecological aspects of IBS

• There is an association between painful periods, pre-menstrual symptoms and IBS.
  
  • Abdominal pain and diarrhoea tend to increase in the pre-menstrual phase.
  • Bloating and constipation tend to increase post-ovulation.
    • Oral contraceptives don't have much effect on bowel function.
    • The effect of hormone replacement therapy hasn't been well studied.
  • Up to 30% of women with IBS report chronic pelvic pain.
    • This is difficult to distinguish from endometriosis - a condition where uterine tissue is present in the pelvic cavity.
    • The accurate diagnosis of endometriosis requires a laparoscopy (inspection of the abdomen and pelvis under GA).
    • Even here there can be confusion as small areas of endometriosis may not be relevant (5-10% of all women have some endometriosis).
    • The majority of symptoms could still be coming from IBS.
  • Painful sexual intercourse and decreased sexual drive are common symptoms in women with IBS (one study suggested 32%).
    • Pain may be part of a generalised tissue sensitivity.
  • The need for surgery should be carefully considered.
    • The rates for hysterectomy, appendicectomy, cholecystectomy are twice as high (or higher) for women with IBS.
    • This may be genuine need but could be a degree of misdiagnosis and "desperation" on the part of patient and doctor.

Sleep and IBS

• Sleep complaints are common.
  • Sleep complaints are associated with anxiety and depression.


• It is uncommon to have sleep disturbed by abdominal pain in IBS - prominent nocturnal pain may suggest another diagnosis.
  • If there is is early morning awakening then the symptoms of IBS may start early.
  • Awakening early in the morning can be a symptom of depression.


• Physiological studies show no abnormalities in the sleep cycle in people with IBS.
  • However dissatisfaction with the quality of sleep and daytime fatigue and tiredness is common.
  • It does seem that this is associated with symptoms of stress and depression.


• The message seems to be that a trial of anti-depressants is worthwhile when tiredness, fatigue and dissatisfaction with sleep are prominent symptoms.
  • Several options  - I prefer paroxetine (Aropax) as there is an effect on anxiety and panic attacks as well.
  • The other option is a small dose of Amitriptyline - this has no mood elevating effect but does help sleep and decreases pain in IBS.

Pain in the butt

Proctalgia fugax

• Severe and sudden attacks of a sharp pain in the rectum.
  • Described as stabbing, burning or grinding pain in the anal canal or rectum.
  • Attacks may follow defaecation, sexual activity or stress.
  • May awake in the middle of the night with severe rectal pain.

Levator ani syndrome

• Continual discomfort on parts of the anal canal or rectum.
  • Described as having the anal canal pulled in knots or feeling like there is a hard object like a golf ball in the anal canal.
  • Women with this problem may have pain on sexual intercourse. Some people report extension of pain across the buttocks and down the legs.

Coccydynia

Paradoxical contraction of the pelvic floor muscles (anismus).

• This an abnormal increase in the pelvic floor muscle activity with defecation (rather than a decrease).
  • This can contribute to constipation or complaints of incomplete evacuation or excessive straining.
  • Excessive pelvic floor activity may be associated with voiding hesitancy, interrupted stream, urinary urge and painful urination.

• Pelvic floor muscle function can be improved by relearning(through biofeedback).
  • Available through specialist colorectal clinics.
  • Several sessions over a few months may be required.
  • Medication does not seem to be effective.

Symptoms that are not part of irritable bowel syndrome

• Awaking at night with diarrhoea or abdominal pain.
  • The abnormal muscular activity of IBS stops at night.
  • Diarrhoea at night may be due to colitis.
    
• Rectal bleeding.
  
  • Rectal bleeding should never to ignored.  Colonoscopy will usually be required to exclude colon cancer.
  • Rectal bleeding may be due to "local" anal causes (anal fissures and internal haemorrhoids). These conditions are aggravated by the variable bowel habit.
• Weight loss
  
  • This may have a simple explanation such as change in eating habits but is not due to IBS per se.
  • There is no problem with absorption of nutrients in IBS even when there is prominent diarrhoea.
    
• Diarrhoea every day (with high stool volume).
  • The typical pattern of IBS is alternating or "swinging" bowel habit with both diarrhoea and constipation (or at least some periods with relatively normal bowel motions).
  • The amount of stool in IBS is actually normal.
  • The key problems in IBS are frequency and urgency of bowel motions on some days (but not every day).
    
• Faecal incontinence loss of control.
  • This can occur partly as a result of IBS (if prominent urgency) but there is usually another reason as well.
  • For example, decrease anal tone e.g could be due to an anal sphincter tear at the time of delivery - the effect can be apparent only in later years.
• Vomiting
  
  • Nausea, particularly in the morning, is common with IBS. The reason for nausea is unclear. Vomiting is not part of IBS.
    
• Difficulty swallowing.  This requires prompt investigation by gastroscopy.
• These are warning symptoms that another diagnosis should be considered.
  Specialist evaluation is important and colonoscopy becomes a crucial investigation without delay.