What Is Irritable Bowel Syndrome?
There are many myths and misunderstandings about irritable bowel syndrome (IBS), from the idea that it only affects women to the notion that it is easily cured by cutting out a few trigger foods.
Here’s a look at what IBS really is, who it affects and how it is diagnosed and treated.
What Is IBS?
IBS is a gut disorder that causes diarrhea, constipation, stomach pain and bloating.
It’s not life-threatening and isn’t caused by physical damage within the bowel, but it can be very painful, embarrassing and have a significant effect on your quality of life.
It can affect patients for years or even decades, although symptoms often wax and wane over time so you may have periods of quite intense symptoms followed by times when you feel fine.
It’s incredibly common, with most estimates suggesting that between 25 and 45 million people in the USA suffer from it. It affects more women than men (with roughly two women diagnosed for every man) and can affect people of any age, although generally, symptoms begin before 50.
Sufferers of a certain age may remember being diagnosed with “spastic colon,” “mucous colitis” or perhaps something vague like “nervous bowel.” These terms have fallen out of favor now as they were never very accurate – IBS is not a type of colitis, and a “nervous disposition" doesn't cause it either! All of these problems would be diagnosed today as IBS.
Types of IBS
All IBS sufferers will have symptoms that affect their gut, but your experience of IBS could be very different from mine. This is because there are three different types of IBS. The type of IBS you are diagnosed with will depend on your most common symptom.
The three different types are:
- Diarrhea-predominant IBS – this is the most famous type of IBS and will apply to you if you have multiple bowel movements per day, often with an urgent need to get to a bathroom quickly and sometimes even bowel incontinence. It is also known as IBS-D for short.
- Constipation-predominant IBS – many people are surprised to learn that IBS sufferers can ever be constipated, but for this group of patients, constipation is their most common symptom. You may have to strain when going to the bathroom, pass hard bowel movements or go days without one. It is also known as IBS-C.
- Alternating or mixed IBS – with this type neither diarrhea nor constipation is more common, but instead, patients suffer from both symptoms and may swing back and forth without ever finding a comfortable middle ground. Also known as IBS-A (or sometimes IBS-M).
It’s important to realize that these groups are based on the predominant symptom, but that doesn’t mean that other symptoms are not experienced.
Patients with IBS-D may sometimes get constipated (and those with IBS-C may get diarrhea), but they will be diagnosed based on the symptoms they suffer from most often.
Overall, each type of IBS is about as common as the others, with about a third of patients suffering from each of the three types. Interestingly, some people find that the type of IBS they suffer from changes over the years so that you might move from IBS-D to IBS-C or vice versa.
You may see references online to “pain-predominant IBS” or IBS-P, where the pain is the most troubling symptom, but it’s not a label that’s often used by doctors.
Some doctors also use IBS-U to refer to unclassified IBS, where patients don’t slot easily into one of the three types, but again it’s not all that commonly used.
The last type of IBS to be aware of is “post-infectious IBS” or IBS-PI.
This label doesn’t describe your symptoms but instead refers to how they started – many people date their IBS back to an episode of food poisoning or gastroenteritis (inflammation of the gut that can cause vomiting and diarrhea).
The link between food poisoning and IBS was discovered during the second world war when men who had been struck down with dysentery didn’t fully recover from their digestive problems.
What Causes IBS?
Unfortunately, no-one knows what causes irritable bowels. We do know that, as mentioned just now, many patients find that their symptoms begin just after a bad stomach bug.
This link has been confirmed by studies of mass outbreaks of food or water poisoning.
Gastroenteritis, E. coli, and Campylobacter
One study examined an outbreak of gastroenteritis caused by E. coli and Campylobacter in contaminated water in Walkerton, Ontario. The outbreak was so serious it killed six people.
Of the other Walkerton residents, 2069 took part in the study and were only accepted if they did not have IBS already.
Two years after the outbreak a massive 36 percent of people who had suffered from gastroenteritis was diagnosed with IBS, whereas just 10 percent of those who had escaped the contamination now had IBS.
Stomach Bugs and Gut Bacteria
It’s thought that a bad stomach bug may alter the balance of good and bad bacteria in the gut that are so important for good digestion.
Additionally, billions of these bacteria may set up home in the small intestine, the first section of the bowel, when most of them are supposed to live only in the colon.
This is called SIBO – small intestinal bacterial overgrowth – and leads to diarrhea or constipation because of the gases given off by the bacteria as they munch on carbohydrates.
Antibiotics, Inflammation, and Gut Pain Sensitivity
Antibiotics may also be part of the cause, again because they could affect the delicate balance of bacteria in the gut and allow the bad bacteria to run impact.
It’s possible that mild inflammation (swelling) is a factor, particularly after an infection has caused inflammation as the body fights the germs.
If the inflammation in the bowel never completely disappears it might lead to IBS. This swelling is not to be confused with inflammatory bowel disease as it is so subtle it wouldn’t show up on a colonoscopy.
There’s been research to show that IBS patients may be more sensitive to gut pain (known as “visceral hypersensitivity”) which means that they may feel pain or discomfort from sensations in the bowel that healthy people wouldn’t notice.
Stress or Anxiety
For a long time, doctors thought that IBS was caused solely by stress or anxiety and labeled it as psychosomatic or all in the head, some buried emotional pain showing up as physical pain.
However, doctors today agree that stress does not cause IBS and it is not a psychological illness.
There’s no doubt that many sufferers find their symptoms are made worse by stress, but that applies to many other illnesses too, it’s not a unique feature of IBS.
What Are the Symptoms of IBS?
The symptoms of IBS are:
- Pain or discomfort in the stomach.
- Diarrhea, with multiple bowel movements per day (often in the morning or after a meal).
- An urgent need for a bowel movement with the possibility of bowel incontinence.
- Constipation, with stools that are hard and/or difficult to pass.
- Feeling like you have not emptied your bowel fully (known as “incomplete evacuation”).
- Mucus in the stool.
- Excess gas.
Some of these IBS symptoms may be relieved by a bowel movement, particularly stomach cramps. The intensity of these symptoms can vary widely from person to person.
Some people will have mild gut problems that can be managed relatively easily, but others may face severe pain, extreme constipation, and diarrhea that is so bad they are unable to live a normal life.
Women may find that their symptoms are much worse just before or during their period due to the influence of hormones.
As well as all the physical symptoms many people struggle with the emotional impact of their illness. Making a desperate run for the bathroom can be immensely embarrassing, and plenty of people react childishly to any talk of poop problems.
This is compounded by some old-fashioned, out of date doctors who see IBS as a mild problem that affects uptight, anxious types who need to relax…
How Is IBS Diagnosed?
There is no medical test for IBS, so doctors use something called the Rome IV Criteria as a guide.
These criteria say that if you have suffered from stomach pain for, on average, at least one day out of every week in the last three months, you may have IBS if you also suffer from at least two of these problems:
- Symptoms that are related to having a bowel movement. For example, the pain might subside once you have been to the toilet.
- You go to the toilet either more or less than usual.
- You notice a change in the look of your stools, for example, they may be thinner or lumpier, looser or more watery.
IBS cannot be diagnosed unless you have suffered from these symptoms for at least six months, so by definition, it’s a long-term disorder, and you won’t receive a quick diagnosis.
In the past, it was common for IBS to be seen as a diagnosis of exclusion. This meant that doctors would test for disorders that could cause similar symptoms like Crohn’s disease and celiac disease and then label the patient with IBS if tests came back negative – they had excluded all other possibilities so it could only be IBS.
However, nowadays more doctors are willing to use the Rome criteria alone which avoids putting patients through unpleasant tests like colonoscopies.
If you have any “red flag” symptoms, then further testing may be a good idea. These are symptoms that are not usually found in IBS like bleeding from the anus, anemia (lack of healthy red blood cells), weight loss, night-time symptoms, fever or first starting to suffer from gut symptoms over the age of 50.
Treatment for IBS
There’s no cure for IBS, and the bad news is that there’s no set treatment plan. Different approaches work for different people, and you may need to experiment with a combination of different treatments before you find relief.
That’s not to say you need to suffer forever, of course, as there are a range of medications, diets, and supplements that are effective for many people, plus psychological treatments that can help to reduce stress and the emotional impact of IBS.
Medications for IBS
Options include over-the-counter remedies for IBS, peppermint oil, and prescription medicines.
The first line of drug treatment includes over-the-counter remedies such as Imodium or Pepto-Bismol for diarrhea and Miralax for constipation.
Anti-spasmodics like Bentyl or Levsin can help to ease crampy feelings by relaxing the muscles in the bowel, although they are not particularly powerful.
Peppermint oil acts as a natural anti-spasmodic for some people, as long as the capsules are enteric-coated – this coating protects the capsules when they are in your stomach but lets them dissolve in the intestine where they are needed.
There have been a handful of prescription drugs available over recent years.
- Lotronex treats diarrhea in women, but its use is now restricted due to fairly rare but serious side effects. You may still be able to get the drug if your diarrhea is so bad it is affecting your quality of life, and you have tried other treatments without success.
- Viberzi is a newer medication which can reduce diarrhea and stomach pain.
- Zelnorm was used briefly to treat constipation but then withdrawn due to heart-related side effects, but Linzess, Amitiza, and Trulance are all available for IBS-C.
- A wide range of laxatives can help, although those that stimulate contractions in the bowel like Exlax or Dulcolax may be quite painful for IBS sufferers and can be too powerful, turning constipation into diarrhea. More gentle alternatives like milk of magnesia draw water into the bowel instead and can work overnight.
- Antibiotics like Xifaxan may help if doctors find that you have an overgrowth of bacteria in your small intestine.
- There is some evidence to show that probiotics can be helpful, as long as the product contains enough bacteria (billions, not millions) and is stored correctly; check the packet to see if it needs to be kept in the fridge.
- If you’ve had your gallbladder removed and suffer from diarrhea, you may benefit from a bile acid binder like Colestid or Welchol.
Fiber and Supplements for IBS
Soluble fiber supplements like Metamucil and Citrucel can be swallowed with water and will help to soften stools and add bulk.
Contrary to popular belief these products are not laxatives in the traditional sense – they may help you go the bathroom if you’re constipated, but they can also reduce diarrhea by firming up soft stools.
There are many different ingredients in these products so you may have to try several before finding the best one for you. They should always be taken with plenty of water.
Calcium has a constipating effect, particularly calcium carbonate, so products like Caltrate Plus can help IBS-D. Magnesium citrate pills have the opposite effect in doses above about 400mg.
If you’re female and find you get diarrhea before or during your monthly cycle it may be due to prostaglandins in the body; choose painkillers like Advil which contain ibuprofen to combat this effect, rather than Tylenol.
Psychological Treatments for IBS
Patients can be understandably reluctant to try psychological treatments because they’ve spent years having their symptoms dismissed as “all in the mind” or feel they are being told their anxiety is the cause of their own illness, when of course many of us are only stressed in the first place because of our messed-up bowels.
However, if there is a strong link between stress in your life and the strength of your symptoms it is worth considering treatments such as cognitive behavioral therapy.
Types of Therapy
- Behavioral therapy can help you to develop robust coping and relaxation strategies and face difficult situations, for example traveling, without becoming overcome with worry and ending up stressing out your bowel as well.
- Gut-directed hypnotherapy was specifically developed to address IBS. A therapist will help you enter a deeply-relaxed state when you should be more receptive to suggestions that help you feel less pain and discomfort.
- Biofeedback involves the use of electrical sensors to monitor how your body is working. It may help to retrain muscles that are tight or tense and allow them to relax and may be useful for constipation.
Different Diets for IBS
The FODMAPs diet involves avoiding some specific carbohydrates present in foods such as wheat, onions, and garlic.
There is lots of evidence to show avoiding FODMAPs can work very well for people with IBS-D or alternating IBS, particularly in reducing pain and bloating, but unfortunately, the diet hasn’t been studied nearly as much in constipation sufferers.
It’s best to follow this diet with the help of a doctor or dietician as it can be quite daunting at first to figure out what you can and can’t eat.
A gluten-free or dairy-free diet is also worth a try as both of these foods are known to cause gut problems. If you’re not having any luck with any of these diets, then try keeping your own food diary of everything you eat and drink and look for links between your diet and your worst IBS days.