Stomach ache: causes and symptoms

When we can’t identify the exact cause of our abdominal pain, it is not uncommon to be overwhelmed by worst-case scenarios. What if we got to know our stomachs better?

Many health problems – some benign, some serious – can lead to stomach pain. Abdominal pain is therefore a frequent reason for clinic and emergency room visits.

Diagnosing a stomach ache can be very complex, because many organs are involved,” explains Dr. Jean-Daniel Baillargeon, gastroenterologist and head of the gastroenterology department at the CIUSSS de l’Estrie – CHUS.

These include the digestive system (stomach, intestines, appendix, pancreas, liver), the urinary system (kidneys, bladder, urinary tract) and the internal genital organs in women (ovaries, fallopian tubes, uterus). Each organ can be affected by various problems: infection, inflammation, blockage, ulcer, cancer…”

But it is not only the ‘contents’ of the belly that can cause pain, the ‘container’ can also cause abdominal pain, such as a pinched nerve or a sore muscle. Then, to complicate matters, organs outside the abdomen sometimes cause radiating pain, so that it can be interpreted as stomach pain: heart attacks, pneumothorax, pleurisy and groin hernia are examples.


Many people complain about food intolerances. Unlike allergy, which causes an immunological reaction (gastrointestinal symptoms, but also skin irritation, facial swelling, breathing difficulties and anaphylactic shock), intolerance causes unpleasant but not dangerous gastrointestinal discomfort (abdominal pain, diarrhoea, constipation, cramps, bloating, etc.).

Among the cases of food intolerance, lactose (milk sugar) is at the top of the list of culprits. People with lactose intolerance can cut out dairy products from their diet, opt for lactose-free versions or take lactase enzyme supplements (Lactaid) to aid digestion.

As for gluten, apart from the 1% of the population who suffer from coeliac disease, many people claim to be intolerant of it. It would be more accurate to talk about wheat intolerance, also known as non-celiac hypersensitivity to gluten,” explains Julie Delorme, a French nutritionist specialising in digestive disorders, food intolerances and allergies.

The latest scientific studies show that the reduction of symptoms in these people is not due to the avoidance of the gluten protein, as has been thought all these years, but to the avoidance of other compounds in wheat, such as its fructans and other proteins.

A team of Australian researchers recently discovered that many people who think they are lactose or wheat intolerant may actually be FODMAP intolerant. This acronym refers to several types of carbohydrates: oligosaccharides (fructans and galactans), disaccharides (lactose), monosaccharides (fructose and excess glucose) and polyols (maltitol, sorbitol, mannitol, etc.).

FODMAPs are found in a variety of foods: wheat, barley, onion, garlic, milk, apple, honey, etc. Poor digestion of these carbohydrates leads to their fermentation in the intestine, which causes many gastrointestinal symptoms, such as abdominal pain, bloating and excessive gas.

“To confirm FODMAP intolerance, it is advisable to reduce the consumption of foods rich in FODMAPs for about a month. If the symptoms diminish, intolerance can be concluded.

After that, it is recommended to do a reintroduction test with each type of carbohydrate to distinguish between those that cause symptoms and those that are tolerated, and thus reduce the number of foods to be avoided to a minimum,” explains Julie Delorme, who was trained by the Australian team. A low FODMAP diet has been shown to alleviate the symptoms of irritable bowel syndrome and inflammatory bowel disease in a large proportion of cases. Since the diet requires significant changes in diet, it is best to consult a nutritionist for help.

In addition, many other food intolerances or sensitivities are possible. “Some people find that they have difficulty digesting one food more than another. They can then exclude it from their diet without too many consequences,” says Dr Jean-Daniel Baillargeon. “Where it becomes dangerous is when people start to accumulate the evictions, without trying to reintroduce the food after a few weeks to validate the return of the symptoms. This can lead to unbalanced diets and nutritional deficiencies,” adds Julie Delorme.


We now know that the brain and the intestines are connected by the vagus nerve and that they communicate constantly through neurotransmitters. What affects one affects the other, and vice versa. “Many studies provide evidence of a link between stressful life events or chronic stress and the intensity of symptoms of functional gastrointestinal disorders,” reports the Canadian Society for Intestinal Research on its website (

Functional disorders are those that, unlike organic diseases, occur without an apparent physical or physiological cause, such as functional dyspepsia and irritable bowel syndrome (IBS). No medical test can detect them, and they cannot be cured by medication or surgery. But the pain is real…

To reduce symptoms, it is important to manage stress better, whether through better time management, physical exercise, changes in lifestyle or relaxation techniques (meditation, yoga, tai chi, qi gong, etc.) and abdominal breathing.

In the case of IBS, studies have shown the effectiveness of psychological, psychotherapy and hypnotherapy treatments in improving disease management and quality of life. Consult the Ordre des psychologues du Québec website ( to find a qualified psychologist or psychotherapist.

Dr. Ghislain Devroede, a specialist in colorectal surgery at the CIUSSS de l’Estrie – CHUS, full professor at the Faculty of Medicine and Health Sciences of the University of Sherbrooke and author of the books Ce que les maux de ventre disent de notre passé and Chacun peut guérir (Éditions Payot), goes further: “Stomach aches often speak of psychological suffering or trauma. As the body and mind are intimately linked, physical symptoms and emotions are communicating vessels. People who suffer from functional gastrointestinal disorders must therefore question their past in order to name what they have repressed or denied. When awareness is gained, it is often the beginning of the healing process.


In the presence of a sudden, acute and unbearable pain, we obviously go to the emergency room, especially if our general state of health deteriorates. Some abdominal pains require emergency intervention, such as appendicitis, ectopic pregnancy or intestinal obstruction. “However, some less severe pains can hide a serious cause; this is why it is recommended to consult a doctor when they are persistent, recurrent or unusual,” says Dr Jean-Daniel Baillargeon.

That said, there is no need to panic at the slightest stomach ache. In the presence of mild or moderate pain, you can first check whether it is due to your diet (too much fat, too much fibre, etc.) or to particular foods (dairy products, alcohol, caffeine, etc.). Painkillers (e.g. Tylenol, Advil) or antacids (e.g. Gaviscon) can also be taken to try to reduce the pain.

Then, since stress is the cause of many stomach aches, stress management techniques, relaxation (yoga, meditation), abdominal breathing and abdominal self-massage can be tried.

If the stomach pain continues for several weeks, it is recommended that the following factors be recorded to help the doctor make a diagnosis:

  • The location of the pain. Is it above or below the belly button? On the right, centre or left side? This helps to target specific organs.
  • The type of pain. Is it diffuse or localised? Sudden or chronic? Moderate or severe? Is it burning, pinching, cramping, twitching?
  • The “schedule” of the pain. Does it occur every day? Does it occur mostly during the day or at night? Does it get worse after meals or when you have an empty stomach, or when you have a bowel movement or urinate?
  • How has the pain changed since it started? When exactly did it start? Has it been increasing or decreasing since its onset? Is it constant, intermittent or cyclical?
  • Factors that reduce or increase the pain (taking antacids, cold compresses, particular positions, stress, etc.).
  • Associated symptoms. For example: fever, constipation, nausea, hives, joint pain, weight fluctuations, loss of appetite, fatigue, etc.

© Unsplash | Sasun Bughdaryan


  • Unusual, persistent or recurrent abdominal pain
  • Blood in the stool or tarry stool
  • Diarrhoea lasting more than a week
  • Vaginal bleeding other than menstrual, unusual vaginal discharge
  • Abdominal pain, especially at night

Abdominal pain accompanied by:

  • severe fatigue, persistent loss of appetite or weight loss
  • unexplained or persistent high fever (more than 48 hours)
  • persistent vomiting (more than 48 hours), especially if there is an inability to drink or eat properly
  • jaundice
  • blood in the urine or a burning sensation when urinating
  • a significant delay in menstruation
  • a palpable lump in the belly


Several gynaecological disorders can cause pain that is mainly in the pelvic area, but sometimes radiates to the abdomen and lower back. Dr. Amélie Bertrand, an obstetrician-gynecologist and assistant professor at the University of Sherbrooke’s Faculty of Medicine, points out some of them.

Uterine fibroids: Located on the wall of the uterus, this non-cancerous tumour is the most common in women of childbearing age. About one third of fibroids can cause bleeding between periods, long and heavy periods, lower abdominal and back pain, swelling of the lower abdomen, pain during intercourse, etc.

Ovarian cysts: In menstruating women, ovarian cysts are common and usually disappear spontaneously. However, 10% to 15% of cysts rupture or twist the ovary, which can cause lower abdominal pain.

Pelvic inflammatory disease: Infection of the female reproductive organs can be caused by bacteria from certain sexually transmitted infections (gonorrhoea and chlamydia) or during an operation inside the womb (fertility treatment, endometrial biopsy and hysteroscopy). It mainly causes pain in the lower abdomen and back, painful urination and intercourse, and abnormal vaginal discharge. It is estimated that two thirds of cases go untreated. However, the possible complications are serious: chronic pelvic pain and fertility problems.

Endometriosis: This is characterised by the presence of endometrial tissue (the lining of the womb) outside the womb, whether on the ovaries, fallopian tubes, bowels, bladder or elsewhere. This condition, which affects about 11% of women of childbearing age, mainly causes chronic pain and fertility problems.

Ovarian cancer: Its symptoms (digestive changes, including swelling and constipation, feeling of pressure or pain in the lower abdomen, palpable mass in the pelvic or abdominal region, pain during sexual intercourse, etc.) usually appear at an advanced stage of the disease. This is why it is important to consult a doctor as soon as they appear, especially if there is a family history of ovarian cancer.

Cervical cancer: Screening with the Pap test has significantly reduced the death rate from this cancer. However, a doctor should be consulted immediately if the following symptoms appear: abnormal vaginal discharge or bleeding, long and heavy periods, pain during sexual intercourse, or pelvic or lower back pain.

For pregnant women, mild stomach pains (heartburn, gastro-oesophageal reflux, constipation, etc.) are very common, as the organs become compressed as the foetus expands in the womb. “If, at the beginning of the pregnancy, you experience severe abdominal cramps or pain, accompanied by bleeding, you should consult a doctor as soon as possible; these symptoms are often linked to a miscarriage or an ectopic pregnancy,” explains the obstetrician-gynaecologist.


The intestines and stomach take up a huge part of our belly. No wonder they are responsible for many of our abdominal discomforts! Here’s a closer look at the most common gastrointestinal diseases.

Functional dyspepsia: This chronic disorder makes digestion difficult and painful (heartburn, early satiety, bloating, acid taste in the mouth, excessive burping, nausea, etc.). It is believed that 20% to 45% of Canadians suffer from functional dyspepsia, but few people seek help.

Inflammatory bowel disease: This is a chronic inflammation of the digestive tract, which includes Crohn’s disease and ulcerative colitis. It mainly causes abdominal pain, cramps, diarrhoea, often bloody stools, weight loss and anaemia.

Irritable bowel syndrome: This disorder, also known as functional colopathy, causes abdominal pain, bloating and alternating constipation and diarrhoea, among other things. In Canadians, the risk of suffering from this condition is 30%. It affects mostly women.

Celiac disease: In some people, the ingestion of gluten (a protein found in wheat, rye and barley) causes an autoimmune reaction that results in malabsorption of nutrients by the body. The most common digestive symptoms include cramps, bloating, diarrhoea and weight loss.

But the disease also causes an increased risk of anaemia, infertility, osteoporosis and cancer, among others. Self-diagnosis is strongly discouraged, as the gluten-free diet is ultra-restrictive and lifelong. The issue can be resolved by obtaining a diagnosis with a simple blood test, provided that it is done before you stop eating gluten.

Colonic diverticulosis: Marked by the presence of diverticula (growths on the outer wall of the colon), it is often asymptomatic. When present, its symptoms resemble those of irritable bowel syndrome, such as alternating episodes of diarrhoea and constipation. The prevalence increases with age, affecting 50% of people aged 50 and over, and 75% of people aged 79 and over.

Colorectal cancer: Colorectal cancer may be asymptomatic in the early stages of the disease. Its symptoms (blood in the stool, changes in bowel habits such as sudden constipation, unexplained weight loss with or without loss of appetite) can also be confused with those of other diseases, so it is important to seek medical attention as soon as they appear. It is the second leading cause of cancer death in Canada.