Gastrointestinal Diseases and Disorders Sourcebook, Fifth Edition

By Omnigraphics

Provides basic consumer health information about the causes, symptoms, diagnosis, and treatment of digestive diseases and disorders of the gastrointestinal tract, including facts about the effects of food intolerances, infections, and certain cancers. Includes index, glossary of related terms, and other resources.

• Language: English
• Publisher: Omnigraphics
• Release date: Jul 1, 2022
• ISBN: 9780780820036

Book preview

Preface

About This Book

Digestive diseases range from a simple upset stomach to life-threatening cancers. Various statistics show that approximately 60–70 million people in the United States have been affected by digestive diseases. According to the National Ambulatory Medical Care Survey (NAMCS), in 2018, 7.9 million Americans were admitted to the emergency departments, and 37.2 million had visited physicians due to various digestive disorders. Improvements in diagnostic and surgical procedures have given hope to people affected with digestive diseases and helped them live longer, healthier, and more productive lives.

Gastrointestinal Diseases and Disorders Sourcebook, Fifth Edition provides basic consumer information about the digestive system and gastrointestinal (GI) diseases and disorders, along with their symptoms, causes, diagnosis, and treatment. It also includes the various types of cancers that affect the GI tract. The book concludes with a glossary of terms related to GI disorders and diseases along with a list of resources for additional help and information.

How to Use This Book

This book is divided into parts and chapters. Parts focus on broad areas of interest. Chapters are devoted to single topics within a part.

Part 1: Introduction to the Digestive System explains the complete function of the digestive system and the common gastrointestinal symptoms and provides tips to keep your gut in check. It also includes a brief discussion of the effects of smoking and medicines on the organs of the digestive system.

Part 2: Diagnostic and Surgical Procedures Used for Gastrointestinal Disorders describes the various types of diagnostic tests used for gastrointestinal disorders that include endoscopic procedures such as virtual colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, diagnostic laparoscopy, and so on. This part also includes upper and lower gastrointestinal surgeries, diagnostic liver tests, and common gastrointestinal surgeries such as ostomy, colectomy, and bariatric procedures.

Part 3: Disorders of the Upper Gastrointestinal Tract discusses in detail the symptoms, causes, diagnosis, treatment, diet, and nutrition of the most common disorders of the upper gastrointestinal tract such as dyspepsia, Barrett esophagus, gastroesophageal reflux disease, dysphagia, peptic ulcers, dumping syndrome, Whipple disease, cyclic vomiting syndrome, and gastroparesis.

Part 4: Disorders of the Lower Gastrointestinal Tract gives a detailed explanation of the most common disorders of the lower gastrointestinal tract such as irritable bowel syndrome, appendicitis, gallstones, diverticulosis and diverticulitis, and colon polyps. It also provides information on congenital and pediatric disorders, structural defects, anorectal disorders, and other disorders such as abdominal adhesions and short-bowel syndrome.

Part 5: Disorders of the Digestive System’s Solid Organs: The Pancreas and Liver talks about the various disorders of the pancreas and liver. Some of these disorders include viral hepatitis, liver cirrhosis, primary sclerosing cholangitis, pancreatitis, Wilson disease, porphyria, hemochromatosis, and type 1 glycogen storage disease.

Part 6: Cancers of the Gastrointestinal Tract discusses the different types of cancers that occur in the gastrointestinal tract along with their causes, prevention, and treatment. The various types of cancer detailed here are esophageal, gastric, liver, anal, colorectal, small intestine, and so on.

Part 7: Food Intolerances and Infectious Disorders of the Gastrointestinal Tract provides an overview of foodborne and waterborne diseases that include infections from Campylobacter, Cryptosporidium, Clostridium difficile, viruses, and so on. It also provides information on lactose intolerance and celiac disease.

Part 8: Additional Help and Information includes a glossary of terms related to gastrointestinal diseases and disorders and a directory of resources for additional support.

Bibliographic Note

This volume contains documents and excerpts from publications issued by the following U.S. government agencies: Centers for Disease Control and Prevention (CDC); Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD); Genetic and Rare Diseases Information Center (GARD); MedlinePlus; National Cancer Institute (NCI); National Center on Birth Defects and Developmental Disabilities (NCBDDD); National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); National Institute of Neurological Disorders and Stroke (NINDS); National Institute on Deafness and Other Communication Disorders (NIDCD); NIH News in Health; Office on Women’s Health (OWH); Surveillance, Epidemiology, and End Results (SEER) Program; and U.S. Food and Drug Administration (FDA).

It also contains original material prepared by Infobase and reviewed by medical consultants.

About the Health Reference Series

The Health Reference Series is designed to provide basic medical information for patients, families, caregivers, and the general public. Each volume provides comprehensive coverage on a particular topic. This is especially important for people who may be dealing with a newly diagnosed disease or a chronic disorder in themselves or in a family member. People looking for preventive guidance, information about disease warning signs, medical statistics, and risk factors for health problems will also find answers to their questions in the Health Reference Series. The Series, however, is not intended to serve as a tool for diagnosing illness, in prescribing treatments, or as a substitute for the physician–patient relationship. All people concerned about medical symptoms or the possibility of disease are encouraged to seek professional care from an appropriate health-care provider.

A Note about Spelling and Style

Health Reference Series editors use Stedman’s Medical Dictionary as an authority for questions related to the spelling of medical terms and The Chicago Manual of Style for questions related to grammatical structures, punctuation, and other editorial concerns. Consistent adherence is not always possible, however, because the individual volumes within the Series include many documents from a wide variety of different producers, and the editor’s primary goal is to present material from each source as accurately as is possible. This sometimes means that information in different chapters or sections may follow other guidelines and alternate spelling authorities. For example, occasionally a copyright holder may require that eponymous terms be shown in possessive forms (Crohn’s disease vs. Crohn disease) or that British spelling norms be retained (leukaemia vs. leukemia).

Medical Review

Infobase contracts with a team of qualified, senior medical professionals who serve as medical consultants for the Health Reference Series. As necessary, medical consultants review reprinted and originally written material for currency and accuracy. Citations including the phrase Reviewed (month, year) indicate material reviewed by this team. Medical consultation services are provided to the Health Reference Series editors by:

Dr. Vijayalakshmi, MBBS, DGO, MD

Dr. Senthil Selvan, MBBS, DCH, MD

Dr. K. Sivanandham, MBBS, DCH, MS (Research), PhD

Health Reference Series Update Policy

The inaugural book in the Health Reference Series was the first edition of Cancer Sourcebook published in 1989. Since then, the Series has been enthusiastically received by librarians and in the medical community. In order to maintain the standard of providing high-quality health information for the layperson the editorial staff at Infobase felt it was necessary to implement a policy of updating volumes when warranted.

Medical researchers have been making tremendous strides, and it is the purpose of the Health Reference Series to stay current with the most recent advances. Each decision to update a volume is made on an individual basis. Some of the considerations include how much new information is available and the feedback we receive from people who use the books. If there is a topic you would like to see added to the update list, or an area of medical concern you feel has not been adequately addressed, please write to: [e-mail].

Part 1 | Introduction to the Digestive System

Chapter 1 | Your Digestive System and How It Works

What Is the Digestive System?¹

The digestive system is made up of the gastrointestinal (GI) tract—also called the GI tract or digestive tract—and the liver, pancreas, and gallbladder. The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus. The hollow organs that make up the GI tract are the mouth, esophagus, stomach, small intestine, large intestine, and anus. The liver, pancreas, and gallbladder are the solid organs of the digestive system (refer to Figure 1.1).

The small intestine has three parts. The first part is called the duodenum. The jejunum is in the middle, and the ileum is at the end. The large intestine includes the appendix, cecum, colon, and rectum. The appendix is a finger-shaped pouch attached to the cecum. The cecum is the first part of the large intestine. The colon is next. The rectum is the end of the large intestine.

Bacteria in your GI tract, also called gut flora or microbiome, help with digestion. Parts of your nervous and circulatory systems also help. Working together, nerves, hormones, bacteria, blood, and the organs of your digestive system digest the foods and liquids you eat or drink each day.

Figure 1.1. Digestive System of the Human Body

Why Is Digestion Important?¹

Digestion is important because your body needs nutrients from food and drink to work properly and stay healthy. Proteins, fats, carbohydrates, vitamins, minerals, and water are nutrients. Your digestive system breaks nutrients into parts small enough for your body to absorb and use for energy, growth, and cell repair.

Proteins break into amino acids.

Fats break into fatty acids and glycerol.

Carbohydrates break into simple sugars.

How Does Your Digestive System Work?¹

Each part of your digestive system helps move food and liquid through your GI tract, break food and liquid into smaller parts, or both. Once foods are broken into small enough parts, your body can absorb and move the nutrients to where they are needed. Your large intestine absorbs water, and the waste products of digestion become stool. Nerves and hormones help control the digestive process. The digestive process of an organ and its movement are shown in Table 1.1.

Table 1.1. Digestive Process

How Does Food Process in Your Body?²

Food undergoes three types of processes in the body:

Digestion

Absorption

Elimination

Digestion and absorption occur in the digestive tract. After the nutrients are absorbed, they are available to all cells in the body and are utilized by the body cells in metabolism.

The digestive system prepares nutrients for utilization by body cells through six activities or functions.

Ingestion

The first activity of the digestive system is to take in food through the mouth. This process, called ingestion, has to take place before anything else can happen.

Mechanical Digestion

The large pieces of food that are ingested have to be broken into smaller particles that can be acted upon by various enzymes. This is mechanical digestion, which begins in the mouth with chewing or mastication and continues with churning and mixing actions in the stomach.

Chemical Digestion

The complex molecules of carbohydrates, proteins, and fats are transformed by chemical digestion into smaller molecules that can be absorbed and utilized by the cells. Chemical digestion, through a process called hydrolysis, uses water and digestive enzymes to break down the complex molecules. Digestive enzymes speed up the hydrolysis process, which is otherwise very slow.

Movements

After ingestion and mastication, the food particles move from the mouth into the pharynx, then into the esophagus. This movement is deglutition or swallowing. Mixing movements occur in the stomach as a result of smooth muscle contraction. These repetitive contractions usually occur in small segments of the digestive tract and mix the food particles with enzymes and other fluids. The movements that propel the food particles through the digestive tract are called peristalsis. These are rhythmic waves of contractions that move the food particles through the various regions in which mechanical and chemical digestion takes place.

Absorption

The simple molecules that result from chemical digestion pass through cell membranes of the lining of the small intestine into the blood or lymph capillaries. This process is called absorption.

Elimination

The food molecules that cannot be digested or absorbed need to be eliminated from the body. The removal of indigestible wastes through the anus, in the form of feces, is defecation or elimination.

How Does Food Move through Your Gastrointestinal Tract?¹

Food moves through your GI tract by a process called peristalsis. The large, hollow organs of your GI tract contain a layer of muscle that enables their walls to move. The movement pushes food and liquid through your GI tract and mixes the contents within each organ. The muscle behind the food contracts and squeezes the food forward, while the muscle in front of the food relaxes to allow the food to move.

Mouth. Food starts to move through your GI tract when you eat. When you swallow, your tongue pushes the food into your throat. A small flap of tissue, called the epiglottis, folds over your windpipe to prevent choking, and the food passes into your esophagus.

Esophagus. Once you begin swallowing, the process becomes automatic. Your brain signals the muscles of the esophagus, and peristalsis begins.

Lower esophageal sphincter. When food reaches the end of your esophagus, a ring-like muscle—called the lower esophageal sphincter (LES)—relaxes and lets food pass into your stomach. This sphincter usually stays closed to keep what is in your stomach from flowing back into your esophagus.

Stomach. After food enters your stomach, the stomach muscles mix the food and liquid with digestive juices. The stomach slowly empties its contents, called chyme, into your small intestine.

Small intestine. The muscles of the small intestine mix food with digestive juices from the pancreas, liver, and intestine and push the mixture forward for further digestion. The walls of the small intestine absorb water and the digested nutrients into your bloodstream. As peristalsis continues, the waste products of the digestive process move into the large intestine.

Large intestine. Waste products from the digestive process include undigested parts of food, fluid, and older cells from the lining of your GI tract. The large intestine absorbs water and changes the waste from liquid into stool. Peristalsis helps move the stool into your rectum.

Rectum. The lower end of your large intestine, the rectum, stores stool until it pushes stool out of your anus during a bowel movement.

How Does Your Digestive System Break Food into Small Parts Your Body Can Use?¹

As food moves through your GI tract, your digestive organs break the food into smaller parts using the following parts:

Mouth. The digestive process starts in your mouth when you chew. Your salivary glands make saliva, a digestive juice, which moistens food, so it moves more easily through your esophagus into your stomach. Saliva also has an enzyme that begins to break down starches in your food.

Esophagus. After you swallow, peristalsis pushes the food down your esophagus into your stomach.

Stomach. Glands in your stomach lining make stomach acid and enzymes that break down food. Muscles of your stomach mix the food with these digestive juices.

Pancreas. Your pancreas makes a digestive juice that has enzymes that break down carbohydrates, fats, and proteins. The pancreas delivers the digestive juice to the small intestine through small tubes called ducts.

Liver. Your liver makes a digestive juice called bile that helps digest fats and some vitamins. Bile ducts carry bile from your liver to your gallbladder for storage or to the small intestine for use.

Gallbladder. Your gallbladder stores bile between meals. When you eat, your gallbladder squeezes bile through the bile ducts into your small intestine.

Small intestine. Your small intestine makes digestive juice, which mixes with bile and pancreatic juice to complete the breakdown of proteins, carbohydrates, and fats. Bacteria in your small intestine make some of the enzymes you need to digest carbohydrates. Your small intestine moves water from your bloodstream into your GI tract to help break down food. Your small intestine also absorbs water with other nutrients.

Large intestine. In your large intestine, more water moves from your GI tract into your bloodstream. Bacteria in your large intestine help break down remaining nutrients and make vitamin K. Waste products of digestion, including parts of food that are still too large, become stool.

What HAPPENS to the Digested Food?¹

The small intestine absorbs most of the nutrients in your food, and your circulatory system passes them on to other parts of your body to store or use. Special cells help absorbed nutrients cross the intestinal lining into your bloodstream. Your blood carries simple sugars, amino acids, glycerol, and some vitamins and salts to the liver. Your liver stores, processes, and delivers nutrients to the rest of your body when needed.

The lymph system, a network of vessels that carry white blood cells (WBC) and a fluid called lymph throughout your body to fight infection, absorbs fatty acids and vitamins.

Your body uses sugars, amino acids, fatty acids, and glycerol to build substances you need for energy, growth, and cell repair.

How Does Your Body Control the Digestive Process?¹

Your hormones and nerves work together to help control the digestive process. Signals flow within your GI tract and back and forth from your GI tract to your brain.

Hormones

Cells lining your stomach and small intestine make and release hormones that control how your digestive system works. These hormones tell your body when to make digestive juices and send signals to your brain that you are hungry or full. Your pancreas also makes hormones that are important to digestion.

Nerves

You have nerves that connect your central nervous system (CNS)—your brain and spinal cord—to your digestive system and control some digestive functions. For example, when you see or smell food, your brain sends a signal that causes your salivary glands to make your mouth water to prepare you to eat.

You also have an enteric nervous system (ENS)—nerves within the walls of your GI tract. When food stretches the walls of your GI tract, the nerves of your ENS release many different substances that speed up or delay the movement of food and the production of digestive juices. The nerves send signals to control the actions of your gut muscles to contract and relax to push food through your intestines.

_____________

This chapter includes text excerpted from documents published by two public domain sources. Text under the headings marked 1 are excerpted from Your Digestive System and How It Works, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), December 2017. Reviewed May 2022; Text under the heading marked 2 is excerpted from Introduction to the Digestive System, Surveillance, Epidemiology, and End Results (SEER) Program, National Cancer Institute (NCI), June 30, 2002. Reviewed May 2022.

Chapter 2 | Keeping Your Gut in Check

Your digestive system is busy. When you eat something, your food takes a twisty trip that starts with being chewed up and ends with you going to the bathroom. A lot happens in between. The health of your gut plays a key role in your overall health and well-being. You can make choices to help your body stay on tract.

Your digestive, or gastrointestinal (GI) tract is a long, muscular tube that runs from your mouth to your anus. It is about 30 feet long and works with other parts of your digestive system to break food and drink down into smaller molecules of nutrients. The blood absorbs these and carries them throughout the body for cells to use for energy, growth, and repair.

With such a long GI highway, it is common to run into bumps in the road. About 60–70 million Americans are affected by digestive diseases, such as gastroesophageal reflux disease (GERD) or irritable bowel syndrome (IBS). GERD happens when your stomach acid and/or contents come back up into your esophagus (swallowing tube) or throat. This causes uncomfortable symptoms such as heartburn and indigestion. IBS is a group of symptoms that include pain in the abdomen and changes in bowel habits. People with IBS may have constipation, diarrhea, or both. Many more people have other digestive problems, like bloating and stomach pain.

There are many factors that can impact gut health, says Dr. Lin Chang, a GI expert at the University of California, Los Angeles. How your body’s built, your family and genetic history, how you manage stress, and what you eat can all affect your gut.

I see a lot of lifestyle-related GI issues, and there are often no quick fixes for that, she says. In general, people do well when they create a more routine schedule, eat a healthy diet and smaller, more frequent meals, add in some exercise, and get a good amount of sleep.

Chang studies the connection between stress and IBS. Her research group has found that people who have early-life stress are more likely to develop IBS. However, this increased risk for IBS went down when people confide in someone they trust about the stress they experienced, she explains. Finding healthy ways to manage stress is important for GI health, and your health overall.

What you eat can help or hurt your digestive system and influence how you feel. Increasing fiber is really important for constipation, says Chang. Most Americans do not eat a lot of fiber so you have to gradually increase the fiber in your diet. Otherwise, you might get gas and more bloating, and would not stick with the changes.

Chang says you should eat at least 20–30 grams of fiber a day for constipation. You can spread out your fiber in small amounts throughout the day. Start with small servings and gradually increase them to avoid gas, bloating, and discomfort.

Try to eat fruits and vegetables at every meal. A variety of fruits, vegetables, whole grains, and nuts can provide a healthy mix of different fibers and nutrients to your diet. An added benefit is that the more fiber and whole foods you eat, the less room you will have for less healthy options.

But some fiber-rich foods, that are high in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) can be hard to digest. Examples include certain fruits and vegetables, dairy products, and wheat and rye products. If you have IBS, your doctor may recommend a diet low in FODMAPs.

Researchers are coming to understand the complex community of bacteria and other microbes that live in the human GI tract called gut flora or microbiota, these microbes help with our digestion. But evidence has been growing that gut microbes may influence our health in other ways too. Studies suggest that they may play roles in obesity, type 2 diabetes, IBS, and colon cancer. They might also affect how the immune system functions. This can affect how your body fights illness and disease. Studies have found that microbes’ effects on the immune system may impact the development of conditions such as allergy, asthma, and rheumatoid arthritis (RA).

You might have heard that probiotics—live microbes that are similar to those found in the human gut—can improve your gut health. These are also called friendly bacteria or good bacteria. Probiotics are available in dietary supplements and in certain foods, such as yogurt.

There is some evidence that probiotics may be helpful in preventing diarrhea associated with antibiotics and improving symptoms of IBS, but more needs to be learned. Researchers still do not know which probiotics are helpful and which are not. They also do not know how much of the probiotics people would have to take or who would most likely benefit from them.

Certain food additives called emulsifiers are something else that may affect your gut health. Emulsifiers are added to many processed foods to improve texture and extend shelf life. But studies show they can affect our gut flora.

Our work and other research indicate that emulsifiers and other food additives can negatively impact the microbiota and promote inflammatory diseases, says Georgia State University’s Dr. Andrew Gewirtz. His group has been studying the relationships between food additives, gut bacteria, and disease in mice. The team also plans to examine how different food additives may affect people.

Based on what his team and others have found, Gewirtz advises, The take home message: Eat a balanced diet and less processed foods.

The GI system is complicated and such an important part of our health, Chang says. It takes a real partnership between patient and doctor to get to the root of issues. Everyone has to find a healthy routine that works for them.

She encourages you to take an active role in finding a doctor who makes you feel comfortable. The right doctor will listen carefully to your health history and symptoms. You can help keep your gut in check by talking with your doctor and—together—making the right choices for you.

_____________

This chapter includes text excerpted from Keeping Your Gut in Check—Healthy Options to Stay on Tract, NIH News in Health, National Institutes of Health (NIH), May 2017. Reviewed May 2022.

Chapter 3 | Common Gastrointestinal Symptoms

Chapter Contents

Section 3.1—Abdominal Pain

Section 3.2—Diarrhea

Section 3.3—Constipation

Section 3.4—Gas in the Digestive Tract

Section 3.5—Bleeding in the Digestive Tract

Section 3.6—Fecal Incontinence

Section 3.1 | Abdominal Pain

Abdominal Pain, © 2022 Infobase. Reviewed May 2022.

Commonly known as stomach pain, tummy ache, belly ache, or cramps, abdominal pain refers to a minor or major ache or discomfort in the stomach area (from below the chest to the pelvic area). It is quite common, and most adults have experienced abdominal pain at some point in their lives. However, abdominal pain is also among the most misdiagnosed conditions in emergency rooms. Stomach discomfort encompasses a wide variety of symptoms that can indicate more than one condition and thus can be misleading. For instance, severe pain or feeling of bloating in the belly may have a cause that is relatively harmless, such as indigestion or menstrual cramping. On the other hand, a minor ache may disguise a serious condition, such as appendicitis. Therefore, it is important to distinguish between the different kinds of abdominal pain and seek medical care when required.

Types of Abdominal Pain

There are several different types of abdominal pain, each of which may indicate a different set of possible medical conditions.

Sharp, Local Pain

This type of pain is probably the most serious and may require immediate medical attention. It occurs as an intense ache in a particular part of the stomach and may result from inflammation or trauma to an internal organ. Among the common conditions that cause sharp, localized pain are appendicitis, pancreatitis, diverticulitis, hernia, and colon cancer.

Dull Ache

This type of pain is common and usually felt over a large part of the belly. The likely causes include indigestion, gas, or a stomach virus.

Cramping

This type of pain is usually a result of gas in the intestinal tract and is not generally worrisome unless it persists for a few days or is accompanied by diarrhea, vomiting, or fever. In this case, it may be food poisoning or gastroenteritis—intestinal inflammation caused by a virus, bacterium, or parasite.

Pain That Comes and Goes

This kind of pain mostly occurs in the upper abdomen. It is usually intense and may start and stop suddenly. Possible causes include kidney stones or gallstones, which require immediate medical attention.

Causes of Abdominal Pain

A host of conditions can result in abdominal pain. Many of the possible causes are simple problems such as overeating, constipation, gas, or nerves, and the symptoms may disappear by themselves over a short period of time. Sometimes, however, abdominal pain may signal a critical condition that warrants urgent medical attention.

Some of the more serious causes of abdominal pain may include food allergies, appendicitis, pancreatitis, diverticulitis, irritable bowel syndrome (IBS), kidney stones, gallstones, ulcers, colon cancer, or pregnancy-related complications. Abdominal pain occasionally may be related to problems outside the abdomen. Stomach aches can be a symptom of heart attack, pneumonia, or problems in the pelvis or groin.

It can be difficult to determine whether abdominal pain is symptomatic of a more serious medical condition. A person who experiences any of the following conditions should contact their medical practitioner:

If your belly feels rigid and is overly sensitive to touch and you also have a fever and are vomiting blood; passing dark, tarry stools; or have bloody diarrhea, these could be a sign of appendicitis, diverticulitis, or bowel obstruction.

If you have sudden, intense pain in the back that slowly descends to the groin, it could be a sign of a kidney- or bladder-related complication.

If you are pregnant and have abdominal pain along with bleeding or vaginal discharge, you may be having a miscarriage or a tubal pregnancy.

If you have pain in the lower right abdomen and are passing stools tinged with blood or mucus, it may be due to inflammation of the colon or large intestine.

If your pain starts in the upper abdomen and moves around to the back or the pain is more pronounced after a fatty meal, it may indicate gallstones.

If you have mild pain in the lower abdomen and discomfort or a burning sensation while urinating, it could be signs of a urinary tract infection (UTI) called cystitis.

If you are a woman and have a constant, dull ache in the lower abdomen along with vaginal discharge, these symptoms may indicate pelvic inflammatory disease (PID), an infection surrounding the ovaries, uterus, and fallopian tubes.

If you have diarrhea along with fever, nausea, or vomiting that lasts more than two days, it may be a case of gastroenteritis. Although most people recover without treatment, prolonged gastroenteritis can lead to dehydration, especially in children.

Diagnosis of Abdominal Pain

To diagnose a patient suffering from abdominal pain, a medical practitioner will take a medical history, perform a physical examination, and conduct investigative tests based on presenting symptoms in order to determine the underlying cause.

When taking the patient’s history, the physician will inquire about the nature of the pain (sharp or dull, localized or general), its location, timing (before or after a meal or related to a particular activity), duration, past occurrences and symptoms, and factors that aggravate or alleviate the pain. It is important that patients provide accurate information in their case histories.

During the physical examination, the physician will feel the patient’s abdomen for signs of tenderness or rigidity. The pelvis and rectum may also be examined for blood or other abnormalities. Next, the physician may order diagnostic tests to pinpoint or rule out certain conditions. Some of the tests that may be conducted include ultrasound, x-ray, computer tomography scan, endoscopy, colonoscopy, blood tests, urine or stool examination, electrocardiogram, or barium enema.

Special Cases of Abdominal Pain

The diagnosis and treatment of abdominal pain may vary depending on the patient’s age, gender, and underlying health conditions. Some circumstances that can affect the causes and symptoms of abdominal pain include the following.

During Pregnancy

Most pregnant women feel some kind of abdominal pain as a consequence of the physiological and hormonal changes that occur during pregnancy. Although it is usually mild and harmless, severe or prolonged pain—or pain accompanied by bleeding—could be an indication of a life-threatening complication such as preeclampsia, miscarriage, or ectopic pregnancy. Immediate medical attention is required in such cases.

In Infants

Abdominal pain with gas may be a result of colic. Other signs of colic include fussiness, inconsolable crying, and pulling the legs up to the abdomen. Though distressful, colic is a relatively harmless condition that goes away as the child gets older. It is important to consult a pediatrician, however, to rule out any other causes of abdominal pain.

In Children

Stomach aches are quite common among young children and are usually a result of minor ailments such as constipation, gas, or stomach flu. In these cases, the symptoms generally go away on their own within a few days. However, if the pain worsens with time or if the child also has fever and nausea, it could be a sign of something more serious that warrants medical attention.

In Teenage Girls

Sharp pain or dull aches in the lower abdomen or lower back may be related to menstrual cramps.

In Cancer Patients

People undergoing chemotherapy for cancer treatment may often feel cramping or dull aches in the abdomen because chemotherapy affects the working of the intestines. It can either slow down or speed up the passage of stool through the bowel, thereby causing constipation or diarrhea and resulting in cramping. Chemotherapy also affects digestion and can cause gas. Some cancer medications can also cause ulcers or other abdominal complications. Cancer patients should seek medical attention if the pain is severe and prolonged and accompanied by other symptoms such as fever, vomiting, or sudden swelling of the abdomen.

Peritonitis

A serious condition involving inflammation or infection of the tissue lining the inner wall of the abdominal cavity. It can be caused by the perforation or rupture of an abdominal organ or the leakage of bodily fluids such as blood, urine, or gastric juices into the peritoneal cavity. Left untreated, peritonitis can cause potentially fatal damage to the liver, kidneys, and other organs. Symptoms of peritonitis include constant, severe abdominal pain that is aggravated by a slight touch or impact.

Prevention and Treatment

To prevent indigestion and abdominal pain, it is important to drink plenty of water and limit the consumption of carbonated beverages. Since dietary fiber aids in digestion and helps prevent constipation, a diet rich in whole grains, fruits, and vegetables can also help people avoid stomach aches. Other tips include eating small meals at regular intervals rather than overeating at a single meal and limiting the intake of fatty, greasy, and high-sodium foods.

There are a variety of home remedies and over-the-counter (OTC) medications available to provide relief from abdominal pain caused by indigestion or constipation. Additional treatments include lying down and taking deep breaths, placing a heating pad or hot water bottle on the belly, and eating mild foods such as bananas, rice, applesauce, and toast. It is important to avoid taking aspirin or other anti-inflammatory drugs, unless prescribed by a doctor, as they may irritate the stomach and worsen symptoms.

References

Abdominal Pain, MedlinePlus, U.S. National Library of Medicine (NLM), 2014.

Abdominal Pain, Short-Term, FamilyDoctor.org, American Academy of Family Physicians (AAFP), 1996.

Section 3.2 | Diarrhea

This section includes text excerpted from Diarrhea, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), December 7, 2016. Reviewed May 2022.

What Is Diarrhea?

Diarrhea is loose, watery stools three or more times a day. Diarrhea may be acute, persistent, or chronic:

Acute diarrhea. It is a common problem that typically lasts one or two days and goes away on its own.

Persistent diarrhea. It lasts longer than two weeks and less than four weeks.

Chronic diarrhea. It lasts at least four weeks. Chronic diarrhea symptoms may be continual or may come and go.

How Common Is Diarrhea?

Diarrhea is a common problem. Acute diarrhea is more common than persistent or chronic diarrhea. Researchers estimate that about 179 million cases of acute diarrhea occur in the United States each year.

What Are the Complications of Diarrhea?

Dehydration

Diarrhea may cause dehydration, which means your body lacks enough fluid and electrolytes to work properly. Your body loses more fluid and electrolytes in loose stools than solid stools.

Malabsorption

Diarrhea may cause malabsorption. If people do not absorb enough nutrients from the food they eat, they may become malnourished. Certain conditions that cause chronic diarrhea—such as infections, food allergies and intolerances, and certain digestive tract problems—may also cause malabsorption.

Symptoms of Diarrhea

What Are the Symptoms of Diarrhea?

The main symptom of diarrhea is passing loose, watery stools three or more times a day.

People with diarrhea may also have one or more of the following symptoms:

An urgent need to use the bathroom

Cramping

Loss of control of bowel movements

Nausea

Abdominal pain

People with diarrhea caused by some infections may also have one or more of the following symptoms:

Bloody stools

Fever and chills

Light-headedness and dizziness

Vomiting

Diarrhea may cause dehydration and malabsorption.

What Are the Symptoms of Dehydration and Malabsorption?

Dehydration and malabsorption can be serious complications of diarrhea. Their symptoms in adults, infants, toddlers, and young children are as follows.

Dehydration

Symptoms of dehydration in adults may include:

Thirst

Urinating less than usual

Fatigue

Dark-colored urine

Dry mouth

Decreased skin turgor

Sunken eyes or cheeks

Light-headedness or fainting

Signs of dehydration in infants, toddlers, and young children may include:

Thirst

Low urine output or no wet diapers for three hours or more

Lack of energy

Dry mouth

No tears when crying

Decreased skin turgor

Sunken eyes, cheeks, or soft spot in the skull

Malabsorption

Symptoms of malabsorption in adults may include:

Bloating

Changes in appetite

Gas

Loose, greasy, foul-smelling bowel movements

Weight loss

Symptoms of malabsorption in infants, toddlers, and young children may include:

Bloating

Changes in appetite

Gas

Loose, greasy, foul-smelling bowel movements

Weight loss or poor weight gain

Causes of Diarrhea

Acute and persistent diarrhea may have causes that are different from those of chronic diarrhea. In many cases, doctors do not find the cause of diarrhea. Most diarrhea goes away on its own within four days, and finding the cause is not necessary.

Acute and Persistent Diarrhea

The most common causes of acute and persistent diarrhea are infections, traveler’s diarrhea, and side effects of medicines.

Infections

Three types of infections that cause diarrhea include:

Viral infections. Many viruses cause diarrhea, including norovirus and rotavirus. Viral gastroenteritis is a common cause of acute diarrhea.

Bacterial infections. Several types of bacteria can enter your body through contaminated food or water and cause diarrhea. Common bacteria that cause diarrhea include Campylobacter, Escherichia coli (E. coli), Salmonella, and Shigella.

Parasitic infections. Parasites can enter your body through food or water and settle in your digestive tract. Parasites that cause diarrhea include Cryptosporidium enteritis, Entamoeba histolytica, and Giardia lamblia.

Infections in the digestive tract that spread through foods or drinks are called foodborne illnesses.

Infections lasting more than two weeks and less than four weeks can cause persistent diarrhea.

Traveler’s Diarrhea

Traveler’s diarrhea is caused by eating food or drinking water contaminated with bacteria, viruses, or parasites. Traveler’s diarrhea is most often acute. However, some parasites cause diarrhea that lasts longer. Traveler’s diarrhea can be a problem for people traveling to developing countries.

Side Effects of Medicines

Many medicines may cause diarrhea. Medicines that may cause diarrhea include antibiotics, antacids containing magnesium, and medicines used to treat cancer.

Chronic Diarrhea

Some infections, food allergies and intolerances, digestive tract problems, abdominal surgery, and long-term use of medicines can cause chronic diarrhea.

Infections

Some infections from bacteria and parasites that cause diarrhea do not go away quickly without treatment. Also, after an infection, people may have problems digesting carbohydrates such as lactose or proteins in foods such as cow’s milk, milk products, or soy. Problems digesting carbohydrates or proteins can prolong diarrhea.

Food Allergies and Intolerances

Allergies to foods such as cow’s milk, soy, cereal grains, eggs, and seafood may cause chronic diarrhea.

Lactose intolerance is a common condition that may cause diarrhea after eating foods or drinking liquids that contain milk or milk products.

Fructose intolerance is a condition that may cause diarrhea after eating foods or drinking liquids that contain fructose, a sugar found in fruits, fruit juices, and honey. Fructose is added to many foods and soft drinks as a sweetener called high-fructose corn syrup.

Sugar alcohols such as sorbitol, mannitol, and xylitol may cause diarrhea in some people. Sugar-free candies and gum often include these sugar alcohols.

Digestive Tract Problems

Digestive tract problems that may cause chronic diarrhea include:

Celiac disease

Crohn’s disease

Irritable bowel syndrome (IBS) and other functional gastrointestinal (GI) disorders

Small intestinal bacterial overgrowth (SIBO)

Ulcerative colitis (UC)

Abdominal Surgery

You may develop chronic diarrhea after abdominal surgery. Abdominal surgery is an operation on the appendix, gallbladder, large intestine, liver, pancreas, small intestine, spleen, or stomach.

Long-Term Use of Medicines

Medicines that must be taken for a long time may cause chronic diarrhea. Some medicines, such as antibiotics, can change the normal gut flora and increase your chances of infection with Clostridioides difficile, a bacterium that can cause chronic diarrhea.

Diagnosis of Diarrhea

How Do Doctors Find the Cause of Diarrhea?

Doctors do not typically need to find a cause of acute diarrhea. If your diarrhea lasts longer than four days or you have symptoms such as fever or bloody stools, your doctor may need to find the cause. Your doctor may use information from your medical and family history, a physical exam, or tests to find the cause of your diarrhea.

Medical and Family History

Your doctor will ask for information about your symptoms, such as:

How long you have had diarrhea

How much stool you have passed

How often you have diarrhea

How your stool looks, such as color or consistency

Whether you have other symptoms along with diarrhea

Your doctor will ask about the foods you eat and the beverages you drink. If your doctor suspects you have a food allergy or intolerance, she or he may recommend that you change what you eat to see if your symptoms improve.

Your doctor will also ask about:

Current and past medical conditions

Prescription and over-the-counter (OTC) medicines

Recent contact with other people who are sick

Recent travel to developing countries

Your doctor may ask whether anyone in your family has a history of conditions that cause chronic diarrhea, such as celiac disease, Crohn’s disease, IBS, lactose intolerance, and ulcerative colitis.

Physical Exam

During a physical exam, your doctor may:

Check your blood pressure and pulse for signs of dehydration.

Examine your body for signs of fever or dehydration.

Use a stethoscope to listen to sounds in your abdomen.

Tap on your abdomen to check for tenderness or pain.

Sometimes, doctors perform a digital rectal exam (DRE). Your doctor will have you bend over a table or lie on your side while holding your knees close to your chest. After putting on a glove, the doctor will slide a lubricated finger into your anus to check for blood in your stool.

What Tests Do Doctors Use to Find the Cause of Diarrhea?

Your doctor may use the following tests to help find the cause of your diarrhea.

Stool Test

Stool tests can show the presence of blood, bacteria, or parasites or signs of diseases and disorders. A health-care professional will give you a container for catching and storing the stool. You will receive instructions on where to send or take the container for analysis.

Blood Tests

A health-care professional may take a blood sample to test for certain diseases or disorders that can cause diarrhea.

Hydrogen Breath Test

This test is used to diagnose lactose intolerance by measuring the amount of hydrogen in your breath. Normally, little hydrogen is detectable in your breath. With lactose intolerance, undigested lactose produces high levels of hydrogen in your breath. For this test, you will drink a beverage that contains a known amount of lactose. You will then breathe into a balloon-type container that measures your breath hydrogen level. If the hydrogen level is high, your doctor will diagnose lactose intolerance.

Fasting Tests

To find out if a food intolerance or allergy is causing your diarrhea, your doctor may ask you to avoid foods with lactose, carbohydrates, wheat, or other ingredients to see whether your diarrhea responds to a change in diet.

Endoscopy

Your doctor may use endoscopy to look inside your body to help find the cause of your diarrhea. Endoscopic procedures include:

Colonoscopy

Flexible sigmoidoscopy

Upper GI endoscopy

Treatment for Diarrhea

How Can You Treat Your Acute Diarrhea?

In most cases, you can treat your acute diarrhea with OTC medicines such as loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol, Kaopectate). Doctors generally do not recommend using OTC medicines for people who have bloody stools or fever—signs of infection with bacteria or parasites. If your diarrhea lasts more than two days, see a doctor right away.

When you have acute diarrhea, you may lose your appetite for a short time. When your appetite returns, you can go back to eating your normal diet.

How Can You Treat Your Child’s Acute Diarrhea?

Over-the-counter medicines to treat acute diarrhea in adults can be dangerous for infants, toddlers, and young children. Talk to a doctor before giving your child an OTC medicine. If your child’s diarrhea lasts more than 24 hours, see a doctor right away.

You can give your child her or his usual age-appropriate diet. You can give your infant breast milk or formula as usual.

How Do Doctors Treat Persistent and Chronic Diarrhea?

How doctors treat persistent and chronic diarrhea depends on the cause. Doctors may prescribe antibiotics and medicines that target parasites to treat bacterial or parasitic infections. Doctors may also prescribe medicines to treat some of the conditions that cause chronic diarrhea, such as Crohn’s disease, IBS, or ulcerative colitis. How doctors treat chronic diarrhea in children also depends on the cause.

Doctors may recommend probiotics. Probiotics are live microorganisms, most often bacteria, that are similar to microorganisms you normally have in your digestive tract. Researchers are still studying the use of probiotics to treat diarrhea.

For safety reasons, talk with your doctor before using probiotics or any other complementary or alternative medicines or practices. If your doctor recommends probiotics, talk with her or him about how much probiotics you should take and for how long.

How Can You Prevent Diarrhea?

You can prevent certain types of diarrhea, such as those caused by infections—including rotavirus and traveler’s diarrhea—and foodborne illnesses.

Infections

You can reduce your chances of getting or spreading infections that can cause diarrhea by washing your hands thoroughly with soap and warm water for 15–30 seconds:

After using the bathroom

After changing diapers

Before and after handling or preparing food

Rotavirus, which causes viral gastroenteritis, was the most common cause of diarrhea in infants before rotavirus vaccines became available. The vaccines have reduced the number of cases of rotavirus and hospitalizations due to rotavirus among children in the United States.

Two oral vaccines are approved to protect children from rotavirus infections:

Rotavirus vaccine, live, oral, pentavalent (RotaTeq). Doctors give infants this vaccine in three doses: at two months of age, four months of age, and six months of age.

Rotavirus vaccine, live, oral (Rotarix). Doctors give infants this vaccine in two doses: at two months of age and at four months of age.

For the rotavirus vaccine to be effective, infants should receive all doses by eight months of age. Infants 15 weeks of age or older who have never received the rotavirus vaccine should not start the series.

Parents or caregivers of infants should discuss rotavirus vaccination with a doctor.

Traveler’s Diarrhea

To reduce the chances of getting traveler’s diarrhea when traveling to developing countries, avoid:

Drinking tap water.

Using tap water to make ice, prepare foods or drinks, or brush your teeth.

Drinking juice or milk or eating milk products that have not been pasteurized—heated to kill harmful microbes, viruses, bacteria, and parasites.

Eating food from street vendors.

Eating meat, fish, or shellfish that is raw, undercooked, or not served hot.

Eating raw vegetables and most raw fruits.

You can drink bottled water, soft drinks, and hot drinks such as coffee or tea made with boiling water.

If you are worried about traveler’s diarrhea, talk with your doctor before traveling. Doctors may recommend taking antibiotics before and during a trip to help prevent traveler’s diarrhea. Early treatment with antibiotics can shorten a case of traveler’s diarrhea.

Foodborne Illnesses

You can prevent foodborne illnesses that cause diarrhea by properly storing, cooking, cleaning, and handling foods.

How Can You Treat or Prevent Dehydration Caused by Diarrhea?

To treat or prevent dehydration, you need to replace lost fluids and electrolytes—called rehydration therapy—especially if you have acute diarrhea. Although drinking plenty of water is important in treating and preventing dehydration, you should also drink liquids that contain electrolytes, such as the following:

Broths

Caffeine-free soft drinks

Fruit juices

Sports drinks

If you are an older adult or have a weak immune system, you should also drink oral rehydration solutions, such as Pedialyte, Naturalyte, Infalyte, or CeraLyte. Oral rehydration solutions are liquids that contain glucose and electrolytes. You can make oral rehydration solutions at home.

How Can You Treat or Prevent Your Child’s Dehydration Caused by Diarrhea?

To treat or prevent dehydration, give your child liquids that contain electrolytes. You can also give your child an oral rehydration solution, such as Pedialyte, Naturalyte, Infalyte, or CeraLyte, as directed. Talk to a doctor about giving these solutions to your infant.

Eating, Diet, and Nutrition for Diarrhea

What Should You Eat If You Have Diarrhea?

If you have diarrhea, you may lose your appetite for a short time. In most cases, when your appetite returns, you can go back to eating your normal diet. Parents and caretakers should give children with diarrhea their usual age-appropriate diet and give infants breast milk or formula.

Your doctor may recommend changing your diet to treat some causes of chronic diarrhea, such as lactose intolerance or celiac disease.

What Should You Avoid Eating If You Have Diarrhea?

You should avoid foods that may make your diarrhea worse, such as:

Alcoholic beverages

Drinks and foods containing caffeine

Dairy products such as milk, cheese, and ice cream

Fatty and greasy foods

Drinks and foods containing fructose

Fruits such as apples, peaches, and pears

Spicy foods

Diet drinks and sugarless gum and candies containing sweeteners such as sorbitol, mannitol, and xylitol

Research shows that following a restricted diet does not help treat diarrhea in most cases. Most experts do not recommend fasting or following a restricted diet when you have diarrhea.

Section 3.3 | Constipation

This section includes text excerpted from Constipation, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), November 13, 2014. Reviewed May 2022.

About Constipation

What Is Constipation?

Constipation is a condition in which a person will have stools that are hard, dry, or lumpy. They might find it difficult or painful to pass stools and will have fewer than three bowel movements.

However, people can have different bowel movement patterns, and only you know what is normal for you.

Constipation is not a disease but may be a symptom of another medical problem. Constipation may last for a short or long time.

Who Gets Constipated?

Certain people are more likely to become constipated, including:

Women, especially during pregnancy or after giving birth

Older adults

Non-Caucasians

People who eat little to no fiber

People who take certain medicines or dietary supplements

People with certain health problems, including functional gastrointestinal disorders

Symptoms of Constipation

What Are the Symptoms of Constipation?

Symptoms of constipation may include:

Fewer than three bowel movements a week

Stools that are hard, dry, or lumpy

Stools that are difficult or painful to pass

Incomplete bowel movement

When Should You See a Doctor?

You should see a doctor if your symptoms do not go away with self-care or you have a family history of colon or rectal cancer.

You should see a doctor right away if you have constipation and any of the following symptoms:

Bleeding from your rectum

Blood in your stool

Constant pain in your abdomen

Inability to pass gas

Vomiting

Fever

Lower back pain

Loss of weight without trying

Causes of Constipation

You may be constipated for many reasons, and constipation may have more than one cause at a time. Causes of constipation may include:

Slow movement of stool through your colon

Delayed emptying of the colon from pelvic floor disorders, especially in women, and colon surgery

Functional gastrointestinal (GI) disorders, such as irritable bowel syndrome (IBS)

Certain Medicines and Dietary Supplements

Medicines and dietary supplements that can make constipation worse include:

Antacids that contain aluminum and calcium

Anticholinergics and antispasmodics

Anticonvulsants—used to prevent seizures

Calcium channel blockers

Diuretics

Iron supplements

Medicines used to treat Parkinson disease (PD)

Narcotic pain medicines

Some medicines used to treat depression

Life Changes or Daily Routine Changes

Constipation can happen when your life or daily routine changes. For example, your bowel movements can change:

If you become pregnant

As you get older

When you travel

When you ignore the urge to have a bowel movement

If you change your medicines

If you change how much and what you eat

Certain Health and Nutrition Problems

Certain health and nutrition problems can cause constipation:

Low fiber intake

Dehydration

Less physical activity

Celiac disease

Nervous system disorders, such as Parkinson disease (PD)

Spinal cord or brain injuries

Conditions that affect metabolism, such as diabetes

Conditions that affect your hormones, such as hypothyroidism

Inflammation linked to diverticular disease or proctitis

Intestinal obstructions, including anorectal blockage and tumors

Anatomic problems of the digestive tract

Diagnosis of Constipation

How Do Doctors Find the Cause of Constipation?

Doctors use your medical and family history, a physical exam, or medical tests to diagnose and find the cause of your constipation.

Medical and Family History

Your doctor will ask you questions about your medical history, such as:

Whether you have ever had surgery to your digestive tract

If you have recently lost or gained weight

If you have a history of anemia

Your doctor also is likely to ask questions about your symptoms, such as:

How often do you have a bowel movement?

How long have you had symptoms?

What do your stools look like?

Do your stools have red streaks in them?

Are there streaks of blood on your toilet paper when you wipe?

Your doctor is likely to ask questions about your routines, such as:

What are your eating habits?

What is your level of physical activity?

What medicines, including supplements and complementary and alternative medicines, do you take?

You may want to track your bowel movements and what your stools look like for several days or weeks before your doctor’s visit. Write down or record the information so you can share it with your doctor.

If you have been constipated a long time, your health-care professional may ask whether anyone in your family has a history of conditions that may cause long-lasting constipation, such as:

Anatomic problems of the digestive tract

Intestinal obstruction

Diverticular disease

Colon or rectal cancer

Physical Exam

During a physical exam, a health-care professional may:

Check your blood pressure, temperature, and heart rate

Check for dehydration

Use a stethoscope to listen to sounds in your abdomen

Check your abdomen for:

Swelling

Tenderness or pain

Masses or lumps

Perform a rectal exam

What Medical Tests Do Doctors Use to Find the Cause of Constipation?

Depending on your symptoms and health, your doctor may first try a treatment to improve your symptoms before using tests.

Lab Tests

Your doctor may use one or more of the following lab tests to look for signs of certain diseases and conditions that may be causing your constipation:

Blood tests can show signs of anemia, hypothyroidism, and celiac disease.

Stool tests can show the presence of blood and signs of infection and inflammation.

Urine tests can show signs of diseases such as diabetes.

Endoscopy

Your doctor may perform an endoscopy to look inside your anus, rectum, and colon for signs of problems in your lower digestive tract.

Endoscopies for constipation include:

Colonoscopy

Flexible sigmoidoscopy

During these two tests, your doctor may also perform a biopsy. A biopsy is a procedure that involves taking small pieces of tissue and examining them under a microscope. A doctor can use a biopsy to look for signs of cancer or other problems.

Colorectal Transit Studies

Your doctor may use bowel function tests called colorectal transit studies to see how well your stool moves through your colon:

Radiopaque markers. An x-ray that tracks radioactive markers while they pass through your digestive system. You swallow capsules with the markers, which take about 3–7 days to come out with a bowel movement.

Scintigraphy. A test that involves eating a meal with a small dose of a radioactive substance. Your doctor tracks the substance using special computers and cameras as the substance passes through your intestines.

Other Bowel Function Tests

Your doctor may also use one or more of the following tests