Download Bile Acid Malabsorption/Diarrhoea

Page 1 of 3
View this article online at: patient.info/health/bile-acid-malabsorptiondiarrhoea-leaflet
Bile Acid Malabsorption/Diarrhoea
Bile acid diarrhoea is common, especially in people who are thought to have irritable bowel
syndrome. Bile acid diarrhoea may be caused by a problem with your bowel. Much more often there
is no other medical problem causing the diarrhoea. Bile acid diarrhoea responds very well to
treatment with a medicine called a bile acid binder. The outcome is usually very good if there is no
other problem with your bowel.
Understanding the gallbladder and bile
Bile is a fluid made in the liver. Bile contains various
substances including bile pigments, bile acids, bile salts,
cholesterol and lecithin. Bile is passed into tiny tubes called bile
ducts. The bile ducts join together (like the branches of a tree)
to form the main bile duct. Bile constantly drips down the bile
ducts, into the main bile duct and then into the gut.
The gallbladder lies under the liver on the right side of the upper
tummy (abdomen). It is like a pouch which comes off the main
bile duct and fills with bile. It is a 'reservoir' which stores bile.
The gallbladder squeezes (contracts) when we eat. This
empties the stored bile back into the main bile duct. The bile
passes along the remainder of the bile duct into the duodenum,
which is the first part of the small bowel (gut) after the
stomach.
The bile then moves with the rest of the bowel contents along
the small bowel. The last part of the small bowel is called the
terminal ileum, which then leads on to the large bowel (colon).
Normally most of the bile acids pass from the terminal ileum back into the bloodstream, ie they are reabsorbed
into the bloodstream.
What is bile acid diarrhoea?
If the bile acids are not reabsorbed into the bloodstream then they enter the large bowel (colon). Bile acids in the
large bowel cause abnormally high levels of water and salts to get into the large bowel from the bloodstream. The
increased amount of water and salts in the large bowel then causes watery diarrhoea.
Bile acid diarrhoea is sometimes called bile acid malabsorption because the diarrhoea is caused by the body
being unable to stop losing water and salts into the bowel.
What causes bile acid diarrhoea?
Bile acid diarrhoea may be caused by a number of diseases affecting the gut, especially the last part of the small
bowel (terminal ileum), which then leads to the large bowel (colon). For example, bowel acid diarrhoea may be
caused if your terminal ileum has to be removed or if you have a condition called Crohn's disease.
Other conditions that may lead to bile acid diarrhoea include having your gallbladder removed (cholecystectomy),
coeliac disease, diseases affecting the pancreas, and after radiotherapy. Bile acid diarrhoea may also be caused
by some medications, including metformin, which is used to treat type 2 diabetes.
Page 2 of 3
However, many people who have bile acid diarrhoea do not have any obvious cause. This is called idiopathic bile
acid diarrhoea, which means the cause is not known.
How common is bile acid diarrhoea?
It is estimated that bile acid diarrhoea affects about 1 in every 100 people. Bile acid diarrhoea is thought to affect
about 1 in 3 people who are diagnosed as having irritable bowel syndrome. Bile acid diarrhoea in which the cause
is unknown (idiopathic bile acid diarrhoea) most often occurs in men and women aged between 30 and 70 years.
What are the symptoms of bile acid diarrhoea?
There is often a long history of diarrhoea. See also separate leaflet called Acute Diarrhoea in Adults.
The diarrhoea is usually watery without any blood. The diarrhoea may occur all of the time (continuous) or come
and go (intermittent). There may be no other symptoms but this will depend on the cause of the bile acid
diarrhoea.
How is bile acid diarrhoea diagnosed?
Bile acid diarrhoea if often diagnosed just by a having trial of a medicine used for treatment (see below). The
medicines are usually very effective and so an improvement of diarrhoea when taking the medicine indicates a
likely diagnosis of bile acid diarrhoea.
However, you will need to have blood tests and a stool (faeces) sample test to see if there are any other causes
for the diarrhoea. There are also some specific tests for bile acid diarrhoea. These tests include:
A test called 75selenium homocholic acid taurine (75SeHCAT), measuring the amount of bile acids in
your stool; or
A blood test for 7a-hydroxy-4-cholesten-3-one (C4). Increased levels indicate bile acid diarrhoea.
What are the treatments for bile acid diarrhoea?
The main treatments for bile acid diarrhoea are a low fat diet and taking a medicine called a bile acid binder. A low
fat diet helps to reduce the symptoms of bile acid diarrhoea. Medicines that bind to bile acids in your gut (bowel)
are usually very effective. Examples of bile acid binder medicines are colestyramine, colestipol or colesevelam.
Colestyramine is the medicine most often used and is usually very effective. Colesevelam has been shown to be
effective if treatment with cholestyramine is not successful.
Other medicines that are used to treat any cause of diarrhoea can also be used to treat bile acid diarrhoea. See
separate leaflet Antidiarrhoeal Medicines for Acute Diarrhoea for more details.
What is the outcome (prognosis)?
Most people with bile acid diarrhoea in which cause is unknown (idiopathic bile acid diarrhoea) respond very well
to treatment with a bile acid binder medicine. However, you may need to continue taking the medicine for a long
time (years) in order to stop the diarrhoea.
Bile acid diarrhoea may be caused by an underlying condition affecting the bowel. The outcome will then depend
on the underlying bowel condition.
Further help & information
BAM Support UK
Web: bamsupportuk.org/Welcome.html
BSM - Bile Salt Malabsorption
Page 3 of 3
Web: www.bile.org.uk/
Further reading & references
Camilleri M; Bile Acid diarrhea: prevalence, pathogenesis, and therapy. Gut Liver. 2015 May 23;9(3):332-9. doi:
10.5009/gnl14397.
Wilcox C, Turner J, Green J; Systematic review: the management of chronic diarrhoea due to bile acid malabsorption.
Aliment Pharmacol Ther. 2014 May;39(9):923-39. doi: 10.1111/apt.12684. Epub 2014 Mar 6.
Barkun AN, Love J, Gould M, et al; Bile acid malabsorption in chronic diarrhea: pathophysiology and treatment. Can J
Gastroenterol. 2013 Nov;27(11):653-9.
Camilleri M; Advances in understanding of bile acid diarrhea. Expert Rev Gastroenterol Hepatol. 2014 Jan;8(1):49-61. doi:
10.1586/17474124.2014.851599. Epub 2013 Nov 25.
Watson L, Lalji A, Bodla S, et al; Management of bile acid malabsorption using low-fat dietary interventions: a useful
strategy applicable to some patients with diarrhoea-predominant irritable bowel syndrome? Clin Med (Lond). 2015
Dec;15(6):536-40. doi: 10.7861/clinmedicine.15-6-536.
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical
conditions. EMIS has used all reasonable care in compiling the information but makes no warranty as to its
accuracy. Consult a doctor or other healthcare professional for diagnosis and treatment of medical conditions.
For details see our conditions.
Original Author:
Dr Colin Tidy
Current Version:
Dr Colin Tidy
Peer Reviewer:
Dr Hayley Willacy
Document ID:
29244 (v1)
Last Checked:
05/05/2016
Next Review:
05/05/2019
View this article online at: patient.info/health/bile-acid-malabsorptiondiarrhoea-leaflet
Discuss Bile Acid Malabsorption/Diarrhoea and find more trusted resources at Patient.
© Patient Platform Limited - All rights reserved.