Subspecialties for Internal Medicine Residents
Learn about internal medicine subspecialisation options and why they are essential for effective patient care.
Let’s start with the basics. What is an internist doctor?
An internal medicine doctor is a physician who deals with a broad spectrum of adult illnesses and specializes in the diagnosis and treatment of chronic illness and disease prevention. They also receive primary care training in other areas of focus, including wellness, substance abuse and mental health treatment.
General internists are often responsible for the lifelong care of their adult patients, taking care of them in an ambulatory scenario and as inpatients in the event of hospitalization. Being a general internist means you can build long-term and rewarding relationships with patients, looking after their wellbeing and health for the duration of their adult life.
General internists are not the only internal medicine doctors however – future practitioners also have the option of pursuing an internal medicine subspecialty, where they undertake training in a particular area of focus. If you would like to learn more about some of these healthcare areas, read on below.
What Is a Subspecialty?
A subspeciality is a more narrow field of expertise that an internal doctor chooses to train and gain experience in. Instead of solely covering general internal medicine, an internal medicine specialist will focus on patients with symptoms or a diagnosis that falls within the chosen subspeciality.
To subspecialize, the doctor must complete a period of training known as a fellowship. Once the training is complete, the doctor can become a practitioner and consultant in their chosen field.
An internal medicine doctor with a subspecialization will often be called upon as a consultant for patients with puzzling or complex diagnostic problems.
List of Internal Medicine Subspecialties
If you’re a qualified doctor in internal medicine, there are many subspecialties in which you can choose to train. The list that follows isn’t exhaustive but will show the most common choices:
Adolescent Medicine
Internist doctors specializing in adolescent medicine deal with adolescent and young adult physical, psychological, social and sexual development. These physicians work with patients who are transitioning from childhood to adulthood. While this may sound similar to pediatrics, adolescent medicine specialists don’t work with children until they reach the age of 10 or 11 years old.
Allergy/Immunology
Physicians who specialize in allergy and immunology deal with the prevention, diagnosis and treatment of disorders with the human immune systems, dealing with health issues such as asthma, allergies and immunologic disorders. This specialization can be clinical, dealing with patients directly, or focused more heavily on research and laboratory work.
Cardiovascular Disease
Also known as cardiologists, these physicians are one of the most well-known internal medicine specialists. Doctors who specialize in the cardiovascular system are experts in diseases of the heart and blood vessels. Cardiologists also focus on preventative measures in treating and managing many conditions, including coronary artery disease, heart rhythm abnormalities and heart failure.
Endocrinology
Endocrinologists are hormone and gland doctors. They are experts in the hormonal regulation of normal physiology, including the pituitary, thyroid, adrenal, pancreas, ovaries/testes and target tissues. This specialty focuses on diseases of the thyroid gland, diabetes and other hormone conditions. The specialization favors doctors with a strong research background, as laboratory tests play a large role in diagnosing and managing these diseases.
Gastroenterology
Gastroenterologists, or Gis, research, diagnose and treat disorders of the digestive system (esophagus, stomach, small intestine, large intestine, pancreas and liver). Some commonly treated conditions include ulcers, liver disease and abdominal pain.
Geriatrics
Geriatric doctors deal primarily with elderly patients. There is no specific age when a person should start seeing a geriatrician; however, these physicians generally see patients aged 80+. This specialization focuses on conditions specific to aging, including preventive medicine, management of patients in long-term care and dementia. A geriatric doctor needs to have a deep knowledge of the aging process and look after the patient’s wellbeing as a whole.
Hematology
Hematologists are experts who specialize in the diagnosis, treatment and prevention of disorders affecting the blood, bone marrow and immunologic, hemostatic and vascular systems. Dealing with variety of very serious disorders, such as hemophilia, anemia and leukemia, these doctors usually work closely with oncology physicians.
Infectious Disease
Infectious disease specialists focus their practice on diagnosing and treating diseases caused by microorganisms. While mild and common infections, such as strep throat and sinus infections, can be dealt with by a primary care physician, infectious disease doctors diagnose and treat chronic and severe disorders such as bone infections and HIV.
Nephrology
Internists who go on to specialize in nephrology focus their practice on treating disorders of the kidney, including those that affect kidney function, kidney stone formation and blood pressure regulation. They work with patients who have mild conditions, as well as those with more complex or advanced diseases.
Oncology
Medical oncologists are most commonly known for treating cancer; however, they also deal with noncancerous tumors. Oncologists usually work closely with surgeons and other physicians to treat cancers, while also administering therapies. Often working closely with long-term patients, this is a good specialization if you enjoy interacting directly with people. Oncologists often go on to focus on certain types of cancer or specific therapies, but begin their journey with a more broad interest.
Pulmonary Disease
Pulmonary specialists treat patients with diseases of the lungs, focusing on respiratory disorders, including asthma, emphysema/chronic bronchitis (also called COPD) and pulmonary hypertension. They also diagnose and treat sleeping problems, with a significant focus on sleep apnea.
Rheumatology
A rheumatologist is a physician who deals with the diagnosis and treatment of diseases that affect the joints, muscles and related tissues. Physical examination skills are the priority for this specialization. Autoimmune diseases, such as rheumatoid arthritis and lupus, are treated by rheumatologists due to the joint pain caused by these conditions.
What Are the Most Popular Internal Medicine Subspecialties?
Cardiology, medical oncology and gastroenterology are among the most popular and competitive subspecialization options for internal medicine doctors, due to the high pay opportunities and competitive nature of the subspecialization fellowship programs.
However, when it comes to choosing a specialization, doctors should consider their own personal interests and skills above the relative popularity of the specific field. If you’re an amazing researcher, something lab-based like allergy/immunology or infectious disease may fit you well. Whereas, if you’re more of a people person, you may prefer more direct care options for individual patients, such as adolescent medicine, geriatrics or oncology.
Indifying and prioritizing your own skills and interests will better ensure that you can meet the intensive training requirements of a subspecialization and build a lasting career.
What Are the Highest Paying Internal Medicine Subspecialties?
According to the 2024 Physician Compensation Report, the internal medicine specialties with the highest average annual compensation in the United States are:
| Cardiology | $565,485 USD |
| Gastroenterology | $514,208 USD |
| Oncology | $479,754 USD |
As with all jobs, the internal medicine subspecialties salary will vary depending on city, state and country, and the physician’s experience. Internal medicine doctors should expect to see their compensation increase as their experience does.
How Do I Choose an Internal Medicine Subspecialty?
For those wondering how they should choose an internal medicine subspecialty, the answer really depends on you. When deciding where to focus your time and training, you should consider what areas of medicine you enjoy, what you hope to achieve and where your natural skills lay.
But no matter where you may one day hope to specialize, Medical University of the Americas can help you get there! Our internationally accredited MD program offers expansive education and hands-on training, instruction from dedicated faculty, clinical rotations in the U.S. and Canada, and individualized support services. Our Doctor of Medicine (MD) graduates go on to practice in the U.S., Canada and internationally.
Want to learn more? Check out this video testimonial from an MUA MD program student:
If you have any questions or would like to discuss admissions opportunities, please be sure to contact us. Or go ahead and apply if you’re ready to get started!
FAQs About Internal Medicine
Internal medicine has more than a dozen subspecialties, each focusing on a specific area of healthcare. These include cardiology, gastroenterology, endocrinology and infectious diseases (among others). Subspecialties allow doctors to develop deep expertise in diagnosing and managing complex conditions within their chosen field.
A fellowship is a period of advanced training that allows doctors to specialize in a particular area of medicine after completing residency. A subspecialty is the specific focus of that training, such as nephrology or rheumatology, within internal medicine. In other words, a fellowship is the process, while a subspecialty is the area of expertise gained.
Yes, doctors can pursue multiple subspecialties by completing additional fellowships in different areas of internal medicine. For example, a physician might train in both pulmonology and critical care medicine to expand their expertise. However, this requires extra years of training and board certification in each subspecialty.
Some of the least competitive internal medicine fellowships tend to be in fields like geriatrics, hospital medicine or palliative care. These areas often have more open positions than applicants, making them more accessible than highly sought-after fields like cardiology or gastroenterology. Despite lower competition, these specialties play a crucial role in patient care and offer rewarding career opportunities.