The gastrointestinal (GI) system is made up of the GI tract plus other organs. The function of the GI system is to process nutrients and energy from food and fluids that you ingest. When you eat and drink, digestion begins when you chew food to break it down into smaller pieces and enzymes within your saliva (excreted from salivary glands) begin to break the foods down into the component parts. Swallowed food and fluids travel down your throat into your oesophagus and then into your stomach. Once within the stomach, the food and fluids are mixed with strong acids that dissolve the solids, and digestive enzymes continue to break the food down.
Patients with gastrointestinal problems have impaired GI system. Digestion of foods can be reduced, so fewer nutrients are converted into a usable form. Alternatively, food may be digested correctly but nutrients may not be absorbed into the bloodstream for use by the body. Finally, food and nutrients may be expelled too soon or specific nutrients and fluids may be lost via the faeces.
Types of gastrointestinal disorders
Some of the most common GI problems are:
- Constipation: Constipation is the difficult passage of stools (bowel movements) or the infrequent (less than three times a week) or incomplete passage of stools. Constipation is usually caused by inadequate fibre in the diet, or a disruption of the regular routine or diet. Constipation causes a person to strain during a bowel movement. It might include small, hard stools, and sometimes causes anal problems such as fissures and haemorrhoids. Constipation is rarely the sign of a more serious medical condition.
- Irritable bowel syndrome (IBS): Irritable bowel syndrome (also called spastic colon, irritable colon, or nervous stomach) is a condition in which the colon muscle contracts more readily than in people without IBS. A number of factors can trigger IBS including certain foods, medicines, and emotional stress. Symptoms of IBS include abdominal pain and cramps, excess gas, bloating, and a change in bowel habits such as harder, looser, or more urgent stools than normal. Often people with IBS have alternating constipation and diarrhoea.
- Anal Fissures: Anal fissures are splits or cracks in the lining of the anal opening. The most common cause of an anal fissure is the passage of very hard or watery stools. The crack in the anal lining exposes the underlying muscles that control the passage of stool through the anus and out of the body. An anal fissure is one of the most painful problems because the exposed muscles become irritated from exposure to stool or air, and leads to intense burning pain, bleeding, or spasm after bowel movements.
- Colitis: There are several types of colitis, conditions that cause an inflammation of the bowel including Infectious colitis, Ulcerative colitis, Ischemic colitis and Radiation colitis. Colitis causes diarrhoea, rectal bleeding, abdominal cramps, and urgency (frequent and immediate need to empty the bowels).
Causes of gastrointestinal disorders
The causes of gastrointestinal problems may be a result of disease such as:
- Mal-absorption disorders
- Gastroenteritis (inflammation of the stomach and small intestine due to viral or bacterial infection from contaminated food, a bad reaction to something you ate or a side effect of a medication)
- Colitis (inflammation of the large intestine that may be triggered by certain foods or bacterial infections)
- Other inflammatory bowel diseases (such as Crohn's disease)
- Ulcers in the stomach or small intestine
- Cancer of the digestive system
- Non-GI disorders and diseases such as depression, Parkinson's disease, diabetes, underactive or overactive thyroid gland
- Previous bowel surgery
Symptoms and signs of gastrointestinal disorders
In addition to symptoms such as diarrhoea, constipation, nausea and vomiting, other symptoms and signs of gastrointestinal problems
and disorders include abdominal pain, indigestion, fatigue, dehydration, GI bleeding, loss of appetite, flatulence and regurgitation.
Treatment of gastrointestinal disorders Treating the underlying cause
An important first step in managing GI problems is to identify and treat any underlying diseases that may be causing the GI symptoms. Similarly, medication-related symptoms may be remedied by stopping treatment or switching to an alternative drug, if feasible. Virus-related problems normally resolve themselves within a few days.
Constipation can be relieved by eating more fibre, drinking plenty of fluids and exercising regularly. Laxatives, which aid the passage of stools, may be required although it is important not to overuse these medications as they can worsen the situation over the long term.
If you have diarrhoea, lost fluids and electrolytes can be replaced by drinking additional fluids. Oral rehydration salts are particularly beneficial as they help replenish lost electrolytes and sugars as well as fluid. During rehydration therapy
it is advisable to avoid sugary foods and drinks as these can trigger further bouts of diarrhoea.
Rehydration therapy is useful for nausea and vomiting. Anti-sickness medications are available that are effective in reducing these symptoms, and may also help your appetite to return.
Obtaining the correct balance and quantities of carbohydrate, protein, fat, fibre, minerals, vitamins, electrolytes and water is essential to your health and well-being. This is particularly important if you are unwell because nutrients help you overcome illness. The aims of nutritional support are to prevent further weight loss, promote weight gain (if required), overcome weakness and tiredness, ensure adequate hydration and promote optimal clinical outcomes. The approach uses specially formulated nutritional products that are taken orally or administered as liquids via tubes into the stomach or small intestine or into the bloodstream.