IBS or Stomach Bug: What’s the Difference?


The gut is a highly sophisticated organ.

Responsible for extracting the majority of vitamins and minerals we need from the food we eat, the sheer workload it deals with on a daily basis is considerable; and we often won’t notice the vital and complex functions which are take place inside it all the time.

Provided everything is functioning normally that is. When the gut encounters problems, it’s a development we’ll come to know about fairly quickly.

Bowel movements are seldom a subject discussed in casual conversation. So, our points of reference with regard to normality might not always be clear and, naturally, when matters do start to go awry, it can be hard to know what constitutes a minor issue, or a problem warranting expert attention.

The majority of us will have encountered gastric flu (more commonly known as a stomach bug) at some point in our lifetime. Nausea, vomiting, loose and increased stool frequency (diarrhoea) and mild fever are common fixtures of this type of infection, which is usually caused by either a virus or bacteria.

Irritable bowel syndrome (IBS), as we’ll discuss in this article, is a condition which some might mistake for an acute illness such as this. But not without understandable reason: IBS affects the same part of the body and causes symptoms which aren’t a million miles away from that of a stomach bug.

The two conditions are however very different.

For the benefit of those who might be experiencing the above symptoms and want to find out more about the nature of IBS, we discussed the subject this week with Dr Nick Read, Chair of the IBS Network.

Diagnostic Criteria

IBS is much more common than many people think. The IBS Network estimates that between 10 and 20 percent of persons living in western countries will at any point in time fulfil the diagnostic criteria for IBS.

So what are these diagnostic criteria?

Abdominal discomfort, which might be abdominal pain or bloating plus a disturbance in bowel habit.’ Dr Read explains. ‘Symptoms should occur at least once a week and have lasted for more than three months and there should be no evidence of another bowel disease such as cancer of the bowel, Crohn’s disease, ulcerative colitis or coeliac disease.

Unlike other illnesses, there is no specific testing method for IBS. Because it presents no obviously identifiable signs in the body besides the above symptoms, diagnosis consists of eliminating other factors.

As Dr Read illustrates: ‘IBS is usually diagnosed by most doctors on the basis of typical symptoms of bowel irritation and no specific cause.

IBS or gastroenteritis?

Symptoms of IBS may come and go and, as discussed above, opportunistic infections can sometimes present signs which are similar. Patients who suspect they have one or the other may be wondering, is it easy to tell them apart?

Yes.’ Dr Read explains. ‘Gastroenteritis is an acute condition, it usually only lasts a few days and is mainly associated with diarrhoea, abdominal pain and nausea. The main difference is the length of time the illness lasts.

It should be noted however that the effects of gastric flu can be present for longer in a minority of cases:

Some people can develop persistent symptoms resembling IBS after an attack of gastroenteritis.’ Dr Read goes on to say. ‘This is more common if the patient is depressed, anxious or has something going on in their life at the time.’

When should I see a doctor?

For many, IBS symptoms may only be a minor irritation; and the private nature of irregular bowel habits may understandably make some reluctant to seek medical advice.

Others may presume that there is little a doctor can do to improve matters.

But this is far from the case. Consulting a GP or expert on the subject can help to reduce the severity of flare-ups or minimise their frequency.

It is also important for those who have not received an IBS diagnosis but are experiencing increased bowel movements to notify their doctor, as it might be indicative of a condition requiring treatment.

Dr Read suggests speaking to a GP:

  • ‘if symptoms are severe and making a person feel very ill,
  • ‘if symptoms are accompanied by weight loss or the passage of blood,
  • or if they have continued for three months for no obvious reason.

He also notes that:

people over the age of 50 who develop a persistent alteration in their bowel habit for no obvious reason should be investigated to rule out bowel cancer.

Following a diagnosis

Those who have been diagnosed with IBS will usually be given plenty of information from their practitioner, and organisations such as the IBS Network also have a wealth of information available.

But for those who have just received a diagnosis, perhaps the first aspect of the condition they’ll want to know about is how it is going to affect their daily life.

How manageable is irritable bowel syndrome, and how likely is it that the condition will require treatment?

IBS may be instigated by life trauma and triggered by emotional stress; worry, change, overwork or anything connected with the original trauma as well as certain components of diet.’ Dr Read explains.

Spicy foods, fatty foods and FODMAPS (foods with fermented sugars) are common culprits when it comes to diet.

Drinks which are high in caffeine, such as coffee and fizzy energy drinks, can exacerbate symptoms too by causing the colon to spasm.

He also goes on to say that taking measures to limit stress is a very important factor for those living with the condition to consider:

IBS may be managed by diet and methods to reduce stress and increase confidence and self efficacy (mindfulness, hypnotherapy, complementary therapies), though people do better when they can understand what brought on their IBS and learn what works for them (self management).’

‘This is what we try to help them do at The IBS Network.’


As with other conditions, no two people are the same; and therefore no one treatment method for IBS fits all.

Medications that can help to reduce the frequency and severity of symptoms related to IBS, such as Mebeverine (an antipasmodic) may be recommended by a doctor in some cases.

But successful management, Dr Read says, is all about identifying how your own body responds to different strategies.

For many patients, it is a matter of understanding their condition and what triggers it and adopting practices that can capture their attention and interest and distract them from their illness.’

This may be collectively regarded as mindfulness, and may include creative activity (drawing, painting, writing, music), exercise (dance, rhythmic movement, yoga, swimming, jogging, walking), complementary therapies and meditation.’

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