Gut Reaction #17: Irritable Bowel Syndrome
IBS is a chronic disorder consisting of abdominal pain or discomfort associated with defaecation and/or accompanied by a change in stool form and frequency (constipation or diarrhoea or both). Usually, the abdominal pain or discomfort is either relieved by defaecation or associated with altered bowel frequency or stool form. Other common symptoms include altered stool passage (straining, urgency, incomplete evacuation); abdominal bloating, passage of mucus, lethargy and low backache.
IBS most often affects people between 16 and 30 years and is at least twice as common in women as in men. It is the most common functional disorder which means that the symptoms are absolutely genuine but are not due to an identifiable disease process or detectable abnormality on investigation. It is thought that IBS affects between 10% and 20% of the general population.
So what causes IBS? The short answer is that nobody knows but there are a few theories. IBS may follow an infection or an episode of food poisoning in about 20% of cases (so-called post-infective IBS) and it is thought therefore that this “insult” may change gut bacteria (microbiota) or alter nerve pathways in the gut. IBS may also be worse at times of stress by altering nerve transmitter (serotonin) levels or lowering the threshold at which individuals are aware of symptoms.
What treatments are available? Well, there are many different treatment options, dependent on the predominant symptom and an individual’s preference.
Many people with diarrhoea and abdominal bloating will respond to a low FODMAP (Fermentable, Oligosaccharides, Disaccharides, Monosaccharides And Polyols) diet or restricting the amount of gluten (non-coeliac gluten sensitivity IBS) or dairy products.
May be used to treat pain (mebeverine, alverine, hyoscine, peppermint oil), to relieve constipation (eg lactose) or decrease diarrhoea (eg loperamide). In subjects with more severe IBS with constipation, linaclotide may be tried. Citalopram, that affects serotonin levels, is particularly effective if pain and bloating are the main symptoms.
Treatment with a probiotic such as Symprove may help individuals with IBS but may take many weeks to do so.
Rifaximin (550mg tds for 2 weeks) led to a marked improvement in bloating, abdominal pain, and loose or watery stools compared with placebo. Most likely mode of action of rifaximin is a reduction in overall bacterial load and bacterial fermentation.
In those whom are unkeen on drugs or fail to respond to dietary measures may respond to cognitive therapy or hypnotherapy. According to NICE, the use of acupuncture and reflexology should not be encouraged for the treatment of IBS.
For more information regarding IBS and treatment options, please do not hesitate to contact Dr. Harris.
Note from Author – This piece was published, in full, in the November edition of So Tunbridge Wells magazine.