What Is a Gastroenterologist?

A GI doctor specializes in diagnosing and treating digestive disorders

A gastroenterologist, or GI doctor, is a healthcare provider who specializes in diagnosing and treating diseases and conditions of the digestive tract and liver. This can include heartburn, stomach ulcers, irritable bowel syndrome (IBS), cirrhosis, and much more.

You may be referred to a gastroenterologist for a variety of reasons, such as if you have gastrointestinal symptoms that do not resolve with typical treatment or you are experiencing sudden, significant symptoms like severe abdominal pain or blood in your stool. You may also see one for routine colorectal cancer screening.

This article gives you an overview of who gastroenterologists are, what they do, and how they differ from primary care providers. It also discusses the symptoms and conditions for which you may need to see a GI doctor.

A massage therapist palpating an abdomen
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What Gastroenterologists Do

GI doctors have an in-depth understanding of digestion, nutrient absorption, gastrointestinal motility (how and how quickly food passes through the body), and the function of the liver in digestion.

Their work involves everything from the evaluation and treatment of digestive disorders to the prevention of disease and the maintenance of good gastrointestinal health.

Practicing GI doctors specialize in issues related to the:

  • Esophagus
  • Stomach
  • Small intestine
  • Colon
  • Rectum
  • Pancreas
  • Gallbladder
  • Bile ducts and liver

These include:

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), 60 to 70 million Americans are affected by a digestive disorder, resulting in over 21 million hospitalizations and 48 million doctor visits each year.

When Should You See a GI Doctor?

Primary care doctors can often treat short-lived gastrointestinal issues, such as occasional constipation or diarrhea. They may also be able to manage cases of heartburn or bloating.

You may, however, be referred to a gastroenterologist if:

  • You are not getting better under your current treatment plan
  • The cause of a disorder cannot be found
  • There is an abnormal finding in a stool test or abdominal X-ray
  • Your symptoms are significant or particularly concerning

Signs and symptoms of gastrointestinal disorders that may prompt a visit to a GI doctor include:

  • Abnormal stool color
  • Anal leakage
  • Bloody stools (hematochezia)
  • Chronic abdominal pain or cramping
  • Chronic constipation or diarrhea
  • Chronic heartburn and indigestion
  • Chronic nausea or vomiting
  • Difficulty swallowing (dysphagia)
  • Excessive bloating or gas
  • Loss of appetite
  • Loss of bowel control
  • Malnutrition
  • Pain when swallowing (odynophagia)
  • Rectal bleeding
  • Sudden changes in bowel habit
  • Unexplained weight loss
  • Yellowing of the eyes and/or skin (jaundice)

Cancer Screening

People 45 and older should be screened for colorectal cancer every 10 years, according to the American College of Gastroenterology (ACG). You may need screening sooner if you have certain risk factors, such as a family history.

Speak to your healthcare team about when you should get a colonoscopy.

How They Diagnose GI Issues

In addition to conducting a physical exam, gathering a symptom history, and reviewing your personal and family medical history, GI doctors use several diagnostic tools.

They are extensive and include lab tests, radiologic studies, directed imaging tests, and tissue studies.

Two examples you may already be familiar with include:

  • Colonoscopy: A long, flexible tube with a camera is inserted into the anus so that the rectum and colon can be viewed on a screen. This may be done if you're experiencing symptoms of rectal or colon cancer, but it is also done to screen for these cancers in the absence of symptoms so that they can be caught early, when they are most treatable.
  • Endoscopy: A similar tube is inserted into the mouth and down through the esophagus so that parts of the digestive system can be examined from the inside.

Others include:

Treatments They Offer

The treatments a gastroenterologist may recommend can range from medications and lifestyle changes to surgery and organ transplantation.

Some of these can be provided by the gastroenterologist; others may require a team of specialists, including surgeons, dietitians, and oncologists.

Lifestyle Modifications

In some cases, lifestyle changes may be all that is needed to improve a digestive issue. This can include:

  • Diet adjustments
  • Increased hydration
  • Changes in eating habits
  • Weight loss
  • Exercise
  • Smoking cessation

These strategies may also be recommended along with medical treatment.


The list of drugs used to treat digestive disorders is extensive and may include antibiotics, antacids, antidiarrheals, proton pump inhibitors (PPIs), H2 blockers, and promotility agents like Reglan (metoclopramide).

Over-the-counter medications like stool softeners, laxatives, fiber supplements, nonsteroidal anti-inflammatory drugs (NSAIDs), and hemorrhoid creams may also be recommended.

A gastroenterologist can prescribe any of these options, as needed.


Various procedures may be used to manage or cure a digestive disorder, each of which can be performed by a gastroenterologist. Examples include:

  • Biliary stenting (used to unblock the bile duct)
  • Gallstone or biliary stone removal (via ERCP or MRCP)
  • Polypectomy (removal of colon polyps via thermal ablation, electrocautery, etc.)

Training and Certification

If finding a new doctor seems like a chore or you are particularly happy with your primary care provider, you may wonder if seeing a gastroenterologist is necessary.

Remember that GI doctors have extra training in their area of expertise. They also see a wider variety and more instances of gastrointestinal disorders than general practitioners, which can help inform more accurate diagnoses and treatment plans.

In most cases, a primary care physician will be the one to refer you to a gastroenterologist—specifically because these specialists have training that they do not.

Providers who are not trained in gastroenterology are five times more likely to miss colorectal cancer during colonoscopy than GI doctors.


Gastroenterologists must undergo training and certification in internal medicine and then pursue additional training gastroenterology, the study of the function and diseases of the digestive system.

Gastroenterologists typically undergo 14 years of education and practical training to achieve a board certification. This includes three years of fellowship training devoted specifically to the diagnosis, management, treatment, and prevention of gastrointestinal diseases.

The fellowship training is overseen by one of several national societies, including the ACG, the American Board of Internal Medicine (ABIM), the American Gastroenterological Association (AGA), and the American Society for Gastrointestinal Endoscopy (ASGE). 

Once the fellowship training is complete, certification can be obtained by passing the gastroenterology board exam administered by the ABIM.


Some gastroenterologists choose to specialize in specific disorders or organ symptom. One of the most common is hepatology, devoted to the study of the liver, which requires an additional one-year fellowship.

Others will partake in fellowships and training in subspecialties such as inflammatory bowel diseases, colorectal cancer, gastrointestinal motility, interventional endoscopy, neurogastroenterology, pediatric gastroenterology, and transplant hepatology, among others.

First Visit Appointment Tips

When you are referred to a gastroenterologist, it's important to be clear about your GI symptoms, including bowel movements, gas, diarrhea, or hemorrhoid pain. This will help your provider to arrive at a diagnosis.

If you have chronic symptoms, keep a journal outlining the time, date, duration, and specifics of each event. Be sure to write down what you were doing at the time, including the foods you ate and whether you were stressed, lying down, or exercising vigorously.

Moreover, ask as many questions as you need to fully understand the procedures and what a test result may or may not mean. Examples include:

  • What do you suspect is causing my symptoms?
  • What tests can you use to confirm this?
  • What is involved in the test?
  • How long will it take to get the results?
  • What can I do in the meantime to control my symptoms?
  • Are there things I am doing that make my symptoms worse?
  • Is my condition something that needs to be managed, or can it be cured?

Keep in mind that the more accurately you describe your symptoms and communicate with your GI doctor, the sooner they will know where to start the investigation.

Before your appointment, check that the gastroenterologist accepts your insurance. If a test or procedure is recommended, check on your coverage and what your exact copay or coinsurance costs will be. Ask about less costly alternatives, discounts, and payment plans if the out-of-pocket costs are too high.

A Word From Verywell

Talk to your primary care physician about seeing a gastroenterologist if you feel you have symptoms that suggest a condition that a GI doctor should check for. Their expertise is key to arriving at a correct diagnosis and receiving the proper treatment.

Frequently Asked Questions

  • How can I find a gastroenterologist?

    If you have not been referred to a specific gastroenterologist, you can find a board-certified specialist near you using the online locator provided by ACG. The DocInfo website of the Federation of State Medical Boards (FSMB) provides a review of a provider's education and professional history.

  • What do FACG and FACP after a doctor's name mean?

    Some gastroenterologists receive special recognition for extraordinary achievements in gastroenterology. Those afforded the honor are declared Fellows of the ACG or ACP, denoted by the letters FACG or FACP after their names.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Digestive Diseases Statistics for the United States.

  2. Shaukat A, Kahi CJ, Burke CA, et al. ACG clinical guidelines: Colorectal cancer screening 2021Am J Gastroenterol. 2021 Mar 1;116(3):458-479. doi: 10.14309/ajg.0000000000001122.

  3. American College of Gastroenterology. Your Doctor has Ordered a Colonoscopy: What Questions Should You Ask?

Additional Reading

By Amber J. Tresca
Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.