Internal medicine

medical specialty dealing with the prevention, diagnosis, and treatment of diseases of internal organs

Internal medicine is the branch and specialty of medicine concerning the diagnosis and nonsurgical treatment of diseases in adults, especially of internal organs.

Doctors of internal medicine, also called "internists", are required to have included in their medical schooling and postgraduate training at least three years dedicated to learning how to prevent, diagnose, and treat diseases that affect adults.

Caring for the whole patient


Internists are trained to solve puzzling diagnostic problems and handle severe chronic illnesses and situations where several different illnesses may strike at the same time.

Subspecialties of internal medicine


Internists can choose to focus their practice on general internal medicine, or may take additional training to "subspecialize" in one of 13 areas of internal medicine, generally organized by organ system. Cardiologists, for example, are doctors of internal medicine who subspecialize in diseases of the heart. The training an internist receives to subspecialize in a particular medical area is both broad and deep. Subspecialty training (often called a "fellowship") usually requires an additional one to three years beyond the standard three year general internal medicine residency. (Residencies come after a student has graduated from medical school.)

In the United States, there are two organizations responsible for certification of subspecialists within the field, the American Board of Internal Medicine, and the American Osteopathic Board of Internal Medicine.

The following are the subspecialties recognized by the American Board of Internal Medicine.[1]

The ABIM also recognizes additional qualifications in the following areas

  • Adolescent medicine[17]
  • Clinical cardiac electrophysiology[18][19]
  • Critical care medicine[20][21]
  • Geriatric medicine[22][23]
  • Interventional cardiology[3][4]
  • Sports medicine[24]
  • Transplant hepatology

Internists may also specialize in allergy and immunology. The American Board of Allergy, Asthma, and Immunology is a conjoint board between internal medicine and pediatrics.

The American College of Osteopathic Internists recognizes the following subspecialties.[25]


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