Becoming a gastroenterologist takes a minimum of 14 years after high school: four years of undergraduate education, four years of medical school, three years of internal medicine residency, and three years of gastroenterology fellowship. It’s one of the longer training paths in medicine, but it leads to a well-compensated specialty with an average annual income of $513,000.
Undergraduate Pre-Med Coursework
Your path starts with a four-year bachelor’s degree. While you can major in anything, you’ll need to complete a set of science prerequisites that medical schools require. The exact courses vary by school, but nearly all expect biology (two semesters with labs), general chemistry (two semesters with labs), physics (two semesters), and biochemistry (at least one semester). Many schools also require or recommend statistics, genetics, and upper-level biology courses like cell biology or microbiology.
Some programs are more flexible than others. A few require as few as 24 total credit hours in math and science without specifying exact courses, while others lay out rigid semester-by-semester requirements. Check the specific prerequisites for each medical school you plan to apply to, since failing to complete even one required course can disqualify your application. You’ll also need to take the MCAT, the standardized exam used for medical school admissions, typically during your junior year.
Medical School
Medical school is a four-year program. The first two years focus on classroom and laboratory instruction in anatomy, physiology, pharmacology, pathology, and other foundational sciences. The final two years shift to clinical rotations, where you work directly with patients in hospitals and clinics across specialties like surgery, pediatrics, psychiatry, and internal medicine.
During rotations, pay close attention to your internal medicine experience. This is where you’ll get your first real exposure to the kind of diagnostic thinking and patient management that defines gastroenterology. Strong performance in internal medicine rotations, along with research involvement in GI-related topics, will strengthen your residency applications.
Internal Medicine Residency
After earning your MD or DO degree, you’ll complete a three-year residency in internal medicine. This is sometimes called “categorical” training, and it builds a broad foundation in adult medicine before you specialize. You’ll rotate through cardiology, pulmonology, infectious disease, nephrology, endocrinology, and other internal medicine subspecialties.
Completing this residency makes you eligible for board certification in internal medicine through the American Board of Internal Medicine (ABIM), which is a prerequisite for entering a gastroenterology fellowship. During residency, you’ll want to pursue research projects, build relationships with GI faculty who can write recommendation letters, and perform well on your internal medicine board exams to be competitive for fellowship positions.
Gastroenterology Fellowship
The fellowship is where you become a gastroenterologist. It requires a minimum of 36 months, with at least 18 of those months spent in direct clinical training. The American College of Gastroenterology’s core curriculum covers the full range of digestive diseases: disorders of the esophagus, stomach, small intestine, colon, liver, pancreas, and biliary system.
A major component of fellowship is learning procedural skills. You’ll train extensively in diagnostic and therapeutic upper endoscopy (examining the esophagus, stomach, and upper small intestine through a scope inserted via the mouth) and colonoscopy (examining the colon and rectum). These procedures aren’t just for looking. During an endoscopy, gastroenterologists take tissue biopsies, remove polyps and tumors, stop internal bleeding, inject medications, place stents to open blocked organs, and drain fluid collections. By the end of fellowship, you need to be independently competent in all of these.
Most fellows also engage in research, whether clinical trials, outcomes studies, or basic science. Programs at academic medical centers typically expect fellows to produce publications and present at national conferences.
Board Certification
To practice as a board-certified gastroenterologist, you must pass the ABIM Gastroenterology Certification Examination. Before you can even sit for it, you need to meet several requirements: prior board certification in internal medicine, completion of your fellowship, demonstration of clinical and procedural competence (verified by your program director), and an unrestricted medical license.
The ABIM evaluates six core competencies: patient care and procedural skills, medical knowledge, practice-based learning, communication skills, professionalism, and systems-based practice. Your fellowship program director and competency committee formally attest that you’ve met these standards before you’re approved to take the exam. After certification, you’ll need to maintain it through the ABIM’s ongoing assessment program, which involves periodic knowledge checks throughout your career.
Optional Subspecialty Training
Some gastroenterologists pursue additional fellowship training to specialize even further. Transplant hepatology, for example, is a one-year fellowship focused on managing patients with severe liver disease before and after liver transplantation, including expertise in immunosuppressive therapy and care of critically ill patients on transplant waiting lists. At some institutions, this training can be integrated into the third year of a standard GI fellowship rather than added as a separate year.
Advanced endoscopy is another common path, adding a year of training in complex procedures like ERCP (a specialized technique for diagnosing and treating problems in the bile ducts and pancreatic duct). Other gastroenterologists develop focused practices in inflammatory bowel disease, motility disorders, or pancreatic diseases, sometimes through formal fellowship tracks and sometimes through clinical experience and additional coursework.
Full Training Timeline
Here’s how the years add up for a standard path:
- Undergraduate degree: 4 years
- Medical school: 4 years
- Internal medicine residency: 3 years
- Gastroenterology fellowship: 3 years
- Optional subspecialty fellowship: 1 year
That’s 14 years of training after high school at minimum, or 15 if you pursue a subspecialty. Most gastroenterologists begin independent practice in their early to mid-30s.
Compensation
Gastroenterology is among the higher-paying medical specialties. In 2024, gastroenterologists earned an average of $513,000 annually, a figure that includes base salary, incentive bonuses, and profit-sharing contributions for full-time physicians. Pay has grown at an average annual rate of 3.7% over the past decade. Compensation varies by setting: private practice gastroenterologists who own endoscopy centers typically earn more than those in academic or hospital-employed positions, though academic physicians may value the research time, teaching opportunities, and institutional resources that come with those roles.