What Does a Gastroenterologist Do?

Medically Reviewed by Zilpah Sheikh, MD on April 11, 2024
6 min read

Gastroenterology is the branch of medicine that focuses on the digestive tract, gallbladder, liver, bile ducts, and pancreas. A doctor who specializes in these fields is called a gastroenterologist, also referred to as a GI specialist or a GI doctor.

Gastroenterologists, sometimes called "gastros" for short, are trained to diagnose and treat problems in your gastrointestinal (GI) tract and liver. These doctors also do routine procedures such as colonoscopies, which look at the inside of your colon. They get 5-6 years of specialized education after medical school. You will often see a gastro after a referral from your regular doctor.

There are several branches of gastroenterology. Within gastroenterology, a gastroenterologist handles the workings of the stomach and intestine, including the digestion and absorption of nutrients, waste removal from the system, and the function of the liver as a digestive organ. Conditions such as irritable bowel syndrome (IBS) and pancreatitis would fall under what a gastroenterologist covers.

Hepatology focuses on the liver, gallbladder, biliary tree, and pancreas. You may be referred to someone in hepatology if you have liver disease resulting from medication, jaundice, or enzyme defects, or if your blood tests indicate liver issues. You may also deal with a hepatologist if you need a liver transplant.

Proctology is the practice of treating the anus, colon, and rectum -- parts of the large intestine.

Gastroenterologist vs. proctologist

A proctologist, known for treating the lower gastrointestinal tract, is now usually referred to as a colorectal surgeon. The term "proctologist" refers to the anus and rectum, while "colorectal" refers to the colon and rectum. Either way, these surgeons specialize in treating all parts of your large intestine.

Colorectal surgeons may do surgeries such as gallbladder removal. They may also treat conditions such as anal fissures, gallstones, constipation, hemorrhoids, hernias, and Crohn's disease.

Gastroenterologists are internists, meaning that they specialize in what’s going on inside the body. Like other physicians, gastroenterologists start their professional education with medical school. Then, they go on to complete their residency and fellowship training.

To become a board-certified gastroenterologist, the requirements include:

  • 3 years of an internal medicine residency
  • Board certification in internal medicine
  • 36 months of fellowship training, including at least 18 months of clinical training
  • Successful completion of the Gastroenterology Certification Exam

Board certification isn’t required for a gastroenterologist to practice, but it's an important credential to look for. It proves that the doctor has expertise and training in the specialty.

Some gastroenterologists may choose to complete an additional year of training in research or patient care. That year can include subspecialty training in areas such as pediatric gastroenterology (care for children’s digestion) or transplant hepatology (care of people who may need liver transplants).

You might go to a gastroenterologist for health concerns with your:

  • Esophagus, the tube that connects your mouth to your stomach
  • Stomach
  • Belly
  • Small intestine
  • Colon
  • Rectum
  • Pancreas
  • Gallbladder
  • Bile ducts
  • Liver

Symptoms to tell your gastroenterologist

Your regular doctor may also refer you to a gastroenterologist if you have:

  • Trouble swallowing
  • Heartburn
  • Food coming back up after you swallow
  • Chronic or severe diarrhea
  • Constipation
  • Unexplained weight gain or weight loss
  • Rectal bleeding
  • Gas
  • Bloating
  • Nausea

These could be minor health concerns or signs of a serious condition. Gastroenterologists have the tools and expertise to diagnose you correctly. A few of the diseases and conditions they manage include:

  • Crohn’s disease
  • Ulcerative colitis
  • Hepatitis
  • Cancer of the esophagus
  • Colon polyps that may turn into cancer

You would also see a gastroenterologist to get a screening colonoscopy or other tests that look inside any part of your gastrointestinal tract.

Gastroenterologists have the tools and expertise to treat various types of diseases, including:

Gastrointestinal diseases

  • Celiac disease
  • Irritable bowel syndrome (IBS)
  • Food allergies and intolerances
  • Diverticulitis
  • Appendicitis
  • Inflammatory bowel disease (IBD)
  • Small intestinal bacterial overgrowth (SIBO)
  • Hemorrhoids
  • Stomach ulcers
  • Colorectal polyps

Pancreatic, biliary, and gallbladder diseases

  • Cholecystitis
  • Gallstones
  • Pancreatitis

Liver diseases

  • Viral hepatitis
  • Toxic hepatitis
  • Fatty liver disease
  • Cirrhosis

Esophageal disorders

  • Esophagitis
  • Difficulty swallowing
  • Gastroesophageal reflux disease (GERD)
  • Hiatal hernias

You may need a nonsurgical procedure when visiting a GI doctor. Some that they perform include:

  • Endoscopy, where an instrument is used to look inside the body in areas such as the stomach or small intestines
  • Ultrasounds, to produce medical imaging using sound or other vibrations
  • Colonoscopies, where an instrument is inserted through the anus to examine the colon
  • Liver biopsy, to assess inflammation and fibrosis, or thickening, in the liver
  • Enteroscopy, the examination of your small intestine
  • Polypectomy, the removal of polyps during an endoscopy

A pediatric gastroenterologist trains to become a pediatrician, and then works 3 more years to earn certification to treat digestive, nutritional, and liver disorders in babies, children, and teens.

If your child has issues with eating, food allergies, or other digestive and abdominal problems, see your pediatrician to get a referral for a pediatric gastroenterologist. Pediatric GI specialists can treat a variety of conditions, including:

Food allergies and intolerances

  • Lactose intolerance
  • Cow's milk protein allergies
  • Irritable bowel diseases
  • Malnutrition
  • Nutrition conditions requiring tube feeding
  • Hirschsprung’s disease
  • Short bowel syndrome

Feeding disorders

  • Infant colic
  • GERD
  • Upper airway and upper digestive tract disorders (aerodigestive disorders)
  • Difficulty swallowing (dysphagia)
  • Indigestion (dyspepsia)
  • Congenital disorders of the esophagus
  • Cyclic vomiting syndrome

Other conditions

  • Liver disease
  • Pancreatic insufficiency
  • Bleeding in the GI tract
  • Celiac disease
  • Cystic fibrosis
  • Chronic constipation or diarrhea

Finding a doctor you can trust is important because you need to be able to be open and honest during your treatment. Especially with a gastroenterologist, where you may be talking about sensitive information, it's important to find someone you can confide in.

Ask your regular doctor for referrals. Your doctor knows you and your medical history, and they're a great place to start.

You can also turn to friends and family for recommendations. It's often easier to find someone through word of mouth than purely relying on internet reviews when possible.

It's also important to consider your health insurance if that's how you'll be paying for treatment. You'll want to find someone in your network. Your provider should have a portal where you can find local doctors who accept your policy.

What to expect at the gastroenterologist

You might visit a gastroenterologist at a hospital, clinic, or private office. Depending on your insurance, you might need a referral from your regular doctor.

The gastroenterologist will ask you about your symptoms and perform a physical exam. This usually involves you lying down on the table and the doctor pressing down on the outside of your belly. They’ll feel for anything unusual, ask you if it hurts, and listen for abnormal sounds.

They may send you for further tests or diagnostic procedures such as a colonoscopy or upper endoscopy, both of which use small cameras to let the doctor view your digestive tract. After making a diagnosis, your GI doctor will discuss your treatment options.

Some people see a gastro once or a few times when they have an acute (sudden) issue. Others may have recurring appointments to manage chronic conditions such as inflammatory bowel disease.

Gastroenterologists specialize in treating your digestive tract and cover everything from irritable bowel syndrome to constipation to liver diseases. There are several branches of gastroenterology, and these doctors may do many nonsurgical procedures if you are referred to them for problems such as gas, bloating, belly pain, or rectal bleeding. It's important to find a GI doctor you can be candid with, so take your time finding the right person to treat your condition.

What conditions does a gastroenterologist treat?

Gastroenterologists cover many conditions, some of which are listed above. They treat anything related to the digestive tract, from food intolerances to liver diseases.

Why would someone need to see a gastroenterologist?

You may be referred to a gastroenterologist for many reasons, such as belly pain, gas, vomiting, and certain conditions that concern your digestive tract. You also may be referred to them for nonsurgical procedures such as an endoscopy.

What does "gastroenterology" mean?

"Gastro" means stomach, "entero" means intestines, and "ology" means a branch of study, so "gastroenterology" means the study of the stomach and intestines.

What is the difference between gastroenterology and a gastroenterologist?

Gastroenterology is the branch of medicine, while a gastroenterologist is the doctor that practices that type of medicine.