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MERCK MANUAL
Consumer Version
HEALTH TOPICS
HEALTHY LIVING
SYMPTOMS
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Digestive Disorders
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Digestive Disorders
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Biology of the Digestive System
Overview of the Digestive System
Throat and Esophagus
Stomach
Small Intestine
Pancreas
Large Intestine
Rectum and Anus
Effects of Aging on the Digestive System
Esophagus
Stomach
Small intestine
Pancreas, liver, and gallbladder
Large intestine and rectum
Symptoms of Digestive Disorders
Overview of Digestive Symptoms
Chest or Back Pain
Treatment
Chronic Abdominal Pain and Recurring Abdominal Pain
Causes
Common physical causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Centrally mediated abdominal pain syndrome
Key Points
Constipation in Adults
Complications
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Diet and behavior
Laxatives
Enemas
Fecal impaction
Essentials for Older Adults
Key Points
Diarrhea in Adults
Complications
Causes
Classification
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Dehydration
Medications
Key Points
Difficulty Swallowing
Complications of difficulty swallowing
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Essentials for Older Adults
Key Points
Fecal Incontinence
Causes
Diagnosis
Treatment
Gas
Causes
Belching
Flatus
Bloating
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Medications
Key Points
Hiccups
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Brief hiccups
Persistent hiccups
Key Points
Indigestion
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Key Points
Loss of Appetite
Lump in Throat
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Key Points
Nausea and Vomiting in Adults
Complications
Causes
Common causes
Less common causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Key Points
Regurgitation and Rumination
Regurgitation
Rumination
Diagnosis
Treatment
Diagnosis of Digestive Disorders
Introduction to Diagnosis of Digestive Disorders
Medical History and Physical Examination for Digestive Disorders
Medical History
Physical Examination
Psychological Evaluation
Acid-Related and Reflux-Related Tests
Catheter-Based Monitoring
Wireless Monitoring
Computed Tomography and Magnetic Resonance Imaging of the Digestive Tract
CT Enterography and MR Enterography
CT Colonography
Endoscopy
Preparation
Screening
Biopsy
Treatment
Complications
Impedance Testing
Intubation of the Digestive Tract
Laparoscopy
Manometry
Nuclear Scans of the Digestive Tract
Bleeding Scan
Gastric Emptying Scan
Meckel Scan
Paracentesis
Stool Occult Blood Tests
Guaiac-Based Stool Test
Fecal Immunochemical Test (FIT)
Genetic Stool Test (FIT-DNA Test)
Ultrasound Scanning of the Abdomen
Video Capsule Endoscopy
X-Ray Studies of the Digestive Tract
Standard X-Rays
Barium X-Ray Studies of the Digestive Tract
Fluoroscopy
Barium enema
Anal and Rectal Disorders
Overview of the Anus and Rectum
Diagnosis
Anal Fissure
Symptoms
Diagnosis
Treatment
Anal Itching
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Hygiene and symptom relief
Key Points
Anorectal Abscess
Symptoms
Diagnosis
Treatment
Anorectal Fistula
Symptoms
Diagnosis
Treatment
Fecal Incontinence
Causes
Diagnosis
Treatment
Foreign Objects in the Rectum
Symptoms
Diagnosis
Treatment
Hemorrhoids
Causes
Symptoms
Complications of hemorrhoids
Diagnosis
Treatment
Levator Syndrome
Symptoms
Diagnosis
Treatment
Pilonidal Disease
Diagnosis
Treatment
Proctitis
Causes
Symptoms
Diagnosis
Treatment
Rectal Prolapse
Diagnosis
Treatment
Bezoars and Foreign Bodies of the Digestive Tract
Bezoars
Risk factors for bezoars
Symptoms
Complications of bezoars
Diagnosis
Treatment
Foreign Bodies in the Digestive Tract
Symptoms
Foreign bodies in the esophagus
Foreign bodies in the stomach and intestines
Foreign bodies in the rectum
Complications of foreign bodies in the digestive tract
Diagnosis
Treatment
Foreign bodies in the esophagus
Foreign bodies in the stomach and intestines
Foreign bodies in the rectum
Diverticular Disease
Definition of Diverticular Disease
Diverticulosis of the Large Intestine
Causes
Symptoms
Complications of diverticulosis
Diagnosis
Treatment
Diverticulitis
Causes
Symptoms
Complications of diverticulitis
Diagnosis
Treatment
Drainage for abscesses
Surgery for diverticulitis
Esophageal and Swallowing Disorders
Overview of the Esophagus
Overview of Esophageal Injuries
Symptoms
Diagnosis and Treatment
Overview of Esophageal Obstructions
Diagnosis
Abnormal Propulsion of Food
Achalasia
Causes
Symptoms
Diagnosis
Treatment
Dysphagia Lusoria
Eosinophilic Esophagitis
Symptoms
Diagnosis
Treatment
Esophageal Pouches (Diverticula)
Zenker diverticula (pharyngeal diverticula)
Midesophageal diverticula (traction diverticula)
Epiphrenic diverticula
Diagnosis
Treatment
Esophageal Ruptures
Symptoms
Diagnosis
Treatment
Esophageal Spasm
Symptoms
Diagnosis
Treatment
Esophageal Webs
Gastroesophageal Reflux Disease (GERD)
Symptoms
Complications of gastroesophageal reflux
Diagnosis
Treatment
Prevention
Hiatus Hernia
Causes
Types
Symptoms
Diagnosis
Treatment
Infection of the Esophagus
Symptoms
Diagnosis
Treatment
Lower Esophageal Ring
Treatment
Mallory-Weiss Syndrome
Symptoms
Diagnosis
Treatment
Propulsion Disorders of the Throat
Gastritis and Peptic Ulcer Disease
Introduction to Gastritis and Peptic Ulcer Disease
Gastritis
Causes
Symptoms
Complications of gastritis
Diagnosis
Treatment
Medications for gastritis
Erosive gastritis
Acute stress gastritis
Other types of gastritis
Helicobacter pylori
Infection
Complications of
H. pylori
infection
Symptoms
Diagnosis
Treatment
Prognosis
Peptic Ulcer Disease
Causes
Symptoms
Complications
Bleeding
Penetration
Perforation
Obstruction
Cancer
Diagnosis
Treatment
Prognosis
Medications for the Treatment of Stomach Acid
Proton Pump Inhibitors
Histamine-2 (H2) Blockers
Antacids
Other Medications for Stomach Acid
Gastroenteritis
Overview of Gastroenteritis
Causes
Viruses
Bacteria
Parasites
Symptoms
Gastroenteritis caused by viruses
Gastroenteritis caused by bacteria
Gastroenteritis caused by parasites
Complications of gastroenteritis
Diagnosis
Treatment
Rehydration
Medications
Probiotics
Prevention
Clostridium perfringens
Food Poisoning
Symptoms
Diagnosis
Treatment
Prevention
Drug-Related Gastroenteritis and Chemical-Related Gastroenteritis
Drugs and Medications
Chemicals
Treatment
E. coli
Gastroenteritis
Types of
E. coli
gastroenteritis
Symptoms
Diagnosis
Treatment
Prevention
Norovirus Gastroenteritis
Symptoms
Diagnosis
Treatment
Rehydration
Medications
Prevention
Rotavirus Gastroenteritis
Symptoms
Diagnosis
Treatment
Rehydration
Medications
Prevention
Staphylococcal Food Poisoning
Symptoms
Diagnosis
Treatment
Prevention
Traveler’s Diarrhea
Symptoms
Diagnosis
Treatment
Prevention
More Information
Gastrointestinal Bleeding
Gastrointestinal Bleeding
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Replacing fluids and blood
Stopping the bleeding
Essentials for Older People
Key Points
Esophageal Varices
Causes
Symptoms
Diagnosis
Treatment
Gastrointestinal Emergencies
Overview of Gastrointestinal Emergencies
Acute Abdominal Pain
Types of Abdominal Pain
Peritonitis
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Key Points
Abdominal Abscesses
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Abdominal Wall Hernias
Types of abdominal wall hernias
Incarceration and strangulation
Sports hernias
Symptoms
Diagnosis
Treatment
Inguinal Hernia
Symptoms
Diagnosis
Treatment
Acute Mesenteric Ischemia
Symptoms
Diagnosis
Treatment
Prognosis
Appendicitis
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Ileus
Symptoms
Diagnosis
Treatment
Intestinal Obstruction
Causes
Strangulation
Symptoms
Diagnosis
Treatment
Ischemic Colitis
Symptoms
Diagnosis
Treatment
Prognosis
Perforation of the Digestive Tract
Causes
Symptoms
Diagnosis
Treatment
Inflammatory Bowel Diseases (IBD)
Overview of Inflammatory Bowel Disease (IBD)
Symptoms
Diagnosis
Treatment
Diet and stress management
Health maintenance
More Information
Crohn Disease
Symptoms
Complications of Crohn disease
Diagnosis
Blood and stool tests
Imaging tests
Colonoscopy
Treatment
General management
Antidiarrheal medications
Aminosalicylates
Corticosteroids
Immunomodulating medications
Biologic agents
Broad-spectrum antibiotics and probiotics
Dietary regimens
Surgery
General management
Severity of symptoms
Fistulas
Maintenance regimens
Prognosis
More Information
Ulcerative Colitis
Symptoms
Complications of ulcerative colitis
Diagnosis
Recurring or severe symptoms of ulcerative colitis
Treatment
General management of ulcerative colitis
Aminosalicylates
Corticosteroids
Immunomodulating medications
Biologic agents
Small-molecule agents
Severity of symptoms
Fulminant colitis (toxic colitis)
Maintenance regimens
Surgery
Prognosis
Colon cancer
More Information
Irritable Bowel Syndrome (IBS)
Irritable Bowel Syndrome (IBS)
Causes
Symptoms
Diagnosis
Treatment
Diet
Medications
Other treatments
More Information
Malabsorption
Overview of Malabsorption
Causes
Digestion problems
Absorption problems
Symptoms
Diagnosis
Celiac Disease
Causes
Symptoms
Adults
Children
Diagnosis
Treatment
Prognosis
More Information
Intestinal Lymphangiectasia
Symptoms
Diagnosis
Treatment
Lactose Intolerance
Causes
Symptoms
Cow's milk allergy
Diagnosis
Treatment
Short Bowel Syndrome
Treatment
Key Points
Small Intestinal Bacterial Overgrowth (SIBO)
Causes
Symptoms
Diagnosis
Treatment
Tropical Sprue
Symptoms
Diagnosis
Treatment
Whipple Disease
Causes
Symptoms
Diagnosis
Treatment
Pancreatitis
Overview of Pancreatitis
Acute Pancreatitis
Causes
Gallstones
Alcohol
Other causes
Symptoms
Complications of acute pancreatitis
Diagnosis
Blood tests
Imaging tests
Other tests
Treatment
Prognosis
Chronic Pancreatitis
Causes
Symptoms
Complications of chronic pancreatitis
Diagnosis
Imaging tests
Pancreatic function tests
Blood tests
Treatment
Pain control
Pancreatic enzyme supplements
Management of diabetes
Tumors of the Digestive System
Anal Cancer
Symptoms
Diagnosis
Treatment
Colorectal Cancer
Risk Factors
Lynch syndrome (hereditary nonpolyposis colorectal carcinoma [HNPCC])
MUTYH polyposis syndrome
Symptoms
Diagnosis
Treatment
After surgery
Prognosis
Prevention
Colorectal Cancer Screening
Colonoscopy
Stool Tests
Sigmoidoscopy
Computed Tomography (CT) Colonography
Screening Tests for Genetic Causes of Colorectal Cancer
Esophageal Cancer
Risk Factors
Symptoms
Diagnosis
Treatment
Prognosis
Esophageal Tumors That Are Noncancerous
Diagnosis
Treatment
Familial Adenomatous Polyposis
Symptoms
Diagnosis
Treatment
Gastrointestinal Stromal Tumors
Symptoms
Diagnosis
Treatment
Pancreatic Cancer
Rare types of pancreatic cancer
Symptoms
Complications of pancreatic cancer
Diagnosis
Treatment
Prognosis
Polyps of the Colon and Rectum
Hereditary conditions that cause intestinal polyps
Symptoms
Diagnosis
Monitoring of Peutz-Jeghers syndrome
Treatment
Prevention
Small-Intestine Cancer
Rare types of small-intestine cancer
Symptoms
Diagnosis
Treatment
Small-Intestine Tumors That Are Noncancerous
Symptoms
Diagnosis
Treatment
Stomach Cancer
Rare types of stomach cancer
Risk Factors
Symptoms
Diagnosis
Treatment
Prognosis
Stomach Tumors That Are Noncancerous