What is Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a condition which comes and goes, usually starting during your 20s or 30s. There are episodes of symptoms which come and go, and no symptoms between flare-ups. The symptoms include vague abdominal discomfort, a sense of fullness sometimes called bloating, spasm-like pains in the tummy that comes in waves, constipation in some, and loose motions or diarrhoea in others. In some people, irritable bowel syndrome is triggered by stress. Some people can identify particular foods associated with a flare-up of their symptoms.

What is the difference between IBS and IBD?

IBS is irritable bowel syndrome which is related to gut sensitivity. IBD is inflammatory bowel disease which is a more serious health condition with active gut inflammation leading to bleeding, diarrhoea, and damage to the bowel walls which can cause permanent scarring and narrowing of the gut. There are two main conditions included in IBD: Crohn's disease and ulcerative colitis.

For further information see NHS - Inflammatory bowel disease.

I think I have IBS - do I need to see a doctor?

It is best to consult a GP to confirm the diagnosis of IBS as it is important to exclude more serious conditions which can sometimes cause similar symptoms. A GP will often be able to make a diagnosis after talking to you about your symptoms and how often you get them. Sometimes they will arrange tests to look for other things. There are no specific tests for IBS.

What causes IBS?

The exact cause is unknown but the guts seem to develop a sensitivity resulting in pain and other symptoms. There may be links with too fast or too slow passage of food through the bowel, gut microbes, the immune system, stress, and also a genetic effect, as often other family members also suffer with IBS.

Does stress cause IBS?

Stress probably doesn't actually cause IBS, but it is often a factor in triggering a flare.

Is IBS hereditary?

There is probably not an IBS gene. However the tendency to IBS does often run in families.

What are the symptoms of IBS?

The main symptoms are:

  • Abdominal pain.
  • Cramping.
  • Flatulence/wind/bloating.
  • Diarrhoea.
  • Constipation.

Some people also experience:

  • Mucous (slime) from the back passage (but not blood).
  • Feeling sick.
  • Backache.
  • Tiredness.
  • Urinary symptoms.

I've had IBS all my life but it seems to have changed?

If your symptoms are changing or you are developing new symptoms you should consult a GP.

In particular:

  • Weight loss without dieting. (People with IBS usually do not lose weight).
  • Constant pain or increasing pain in one spot (the pain of IBS usually comes and goes during a flare up and disappears completely between flare ups).
  • Worsening constipation suggesting a blockage of the bowel.
  • New symptoms of blood in the motions (stools). IBS can cause diarrhoea but not blood.
  • Nausea or loss of appetite.
  • Looking pale and tired.
  • Running a temperature (fever).

Is IBS dangerous?

IBS itself is not a dangerous condition. However the symptoms can be similar to those of more serious illnesses including diverticulitis, bowel cancer, ovarian cancer, and other bowel conditions. It is important to consult with a GP to confirm the initial diagnosis and also if symptoms change.

Does IBS lead to bowel cancer?

No. IBS does not lead to bowel cancer.

People with Inflammatory Bowel Disease (IBD) are at increased risk of developing bowel cancer.

New IBS and changed symptoms in IBS (especially bleeding) should be checked by your doctor, as there can be some similar symptoms between IBS and bowel cancer.

Is there bowel bleeding with IBS?

No. Irritable Bowel syndrome does not cause bleeding from the bowel. If you have bleeding consult a GP.

Does diet help IBS?

Yes. A lot of the symptoms of IBS can be helped by a careful diet. There is a useful fact sheet here: British Dietetic Association - Irritable Bowel Syndrome (IBS) and Diet : Food Fact Sheet.

Do probiotics help IBS?

Some people benefit from probiotics such as live yoghurts or fermented milk drinks. An initial trial should last at least 4 weeks. A 2014 study report showed the lesser known brands Symprove and VSL-3 were the most effective probiotics. See also NHS - Probiotics.

Does IBS cause lactose intolerance?

No. IBS does not cause lactose intolerance.

However, the symptoms of lactose intolerance are similar to those of IBS. Lactose intolerance can develop after an episode of infectious diarrhoea (gastroenteritis). It causes a reaction to milk sugars with diarrhoea, abdominal pain, and bloating. The symptoms are triggered by consuming dairy products, e.g. milk (including goats milk), cheese, ice cream, yoghurts, etc.

Do IBS medications contain lactose and sucrose or gelatine?

Yes. Some IBS products from Dr Fox do contain lactose, sucrose, or gelatine. Most capsule medications contain gelatine.

Lactose Sucrose Gelatine
Buscopan No Yes No
Colofac tablets Yes Yes Yes
Colofac capsules No No Yes
Colpermin No No Yes
Fybogel Mebeverine No No No
Loperamide Yes No Yes
Spasmonal No No Yes
Spasmonal Forte No No Yes

Does Colpermin contain peanut oil?

Yes. Colpermin contains peanut (arachis) oil and should not be taken by anyone with peanut allergy.

How do IBS treatments work?

Most IBS medications, supplied by Dr Fox, work by relaxing the muscles in the bowel wall so relieving the symptoms of bloating, abdominal pain, wind, and diarrhoea.

Loperamide to treat disabling diarrhoea in IBS, works by slowing the passage of the contents through the bowel.

See also individual product pages:

Which is the best IBS medication?

Choose your IBS medication according to your most troubling symptoms - see IBS medical information page. No one medication is better than the others, but individuals will find that one type works better for them personally.

Compare IBS treatments
Product Spasm & pain Wind & bloating Diarrhoea Constipation Dose
Colofac Yes Yes Yes No 1 capsule 3 x daily 20 mins before meals, or 1 slow release capsule twice daily
Colpermin Yes Yes No No 1 capsule 2-3 x daily with water
Fybogel Mebeverine Yes Yes No Yes 1 sachet in a glass of water 2-3 x daily 30 mins before meals
Spasmonal Yes Yes Yes No Spasmonal 1 or 2 capsules 2-3 x daily, Spasmonal Forte 1 capsule twice daily
Buscopan Yes Yes Yes No 1-2 tablets up to 4 x daily
Loperamide Yes No Yes No At start 2 capsules then 1 as needed up to max of 6 per day

I get really bad diarrhoea with my IBS - what is best for me?

Buscopan, Colofac, and Spasmonal can all help with diarrhoea/loose stools as they calm spasms in the bowel. However if the diarrhoea is several times a day and very incapacitating, then loperamide is more likely to control it.

Can I take loperamide with other IBS treatments?

Loperamide can be taken with other antispasmodic IBS treatments as it works in a different way to stop diarrhoea.

Loperamide for diarrhoea should not be taken at the same time as Fybogel Mebeverine for constipation.

Can I take two antispasmodics together?

No. Two (or more) antispasmodics should not be used at the same time.

When should you consult your doctor?

You should consult your doctor when your symptoms first develop (especially if over 40 years old) to confirm the diagnosis of IBS.

Also consult your doctor if your symptoms change or you have or develop:

  • Weight loss without dieting.
  • New symptoms of blood in your stool or motions.
  • Nausea or loss of appetite or vomiting.
  • Been pale and tired.
  • A high temperature (fever).
  • Recently travelled abroad (possible tropical bowel disease).
  • IBS symptoms in pregnancy.
  • Constant pain or increasing pain in one spot (the pain of IBS usually comes and goes during a flare-up and disappears completely between flare-ups).
  • Worsening constipation suggesting a blockage of the bowel.

Can exercise help IBS?

Yes. The bowel responds well to exercise and it can help to settle IBS. You should aim for 30 minutes of moderate exercise at least 5 days per week.

What is a sensitive gut?

Sensitive gut is a term that is sometimes used to describe the reaction of the bowel in IBS. People with IBS have a bowel which is sensitive to all sorts of triggers including particular foods, stress, gut microbes, etc. They then develop symptoms of IBS.

IBS treatment

Dr Amanda Wood

Authored 28 January 2022 by Dr Amanda Wood
MB ChB Manchester University 1984. Former NHS GP in Bristol. GMC no. 2855422

Reviewed by Dr C. Pugh, Dr B. Babor
Last reviewed 28 January 2022
Last updated 17 May 2024