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History of Internal Medicine

I.M. the cornerstone of comprehensive health care

Discover the unique leadership roles, career pathways and impact of internal medicine physicians.

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Although internal medicine is often described as the specialty that focuses on the care of adult patients, that definition belies the interesting origins, the rich history, and the specific features that make internal medicine such an important part of medicine today.

The underpinnings of internal medicine began in Germany in the late 1800’s when the amount of medically-related basic science knowledge (such as physiology, pathology, and bacteriology) increased significantly.  There emerged a group of physicians who dedicated themselves to applying this fundamental knowledge to the care of their patients, which differed substantially from the way medicine was practiced at the time which was mostly observational and empiric. These physicians with a “scientific attitude” focused their efforts toward caring for and studying patients with “internal” diseases (as opposed to those specifically with external/cutaneous manifestations); both the approach and the name stuck and characterized internal medicine as it developed as a specialty.

Perhaps the most seminal figure in the development of internal medicine in the United States was William Osler (pronounced Ōsler). Many consider Osler to be the consummate internist, embodying the personal and professional attributes that distinguish internal medicine from other medical specialties. Born in 1849, he demonstrated an extraordinary commitment to patient care and a ceaseless effort to apply scientific knowledge to clinical practice. He also developed a unique approach (at the time) of teaching and learning medicine structured around patients, including an emphasis on bedside teaching and the use of clinical clerkships for medical students and residency training for those who had graduated from medical school – these educational methods have remained relatively intact since they were introduced over a century ago. Much can be learned about what makes internal medicine unique by reading Osler’s writings and observations on being a physician and caring for patients.

Since Osler’s time, internal medicine’s commitment to a “scientific attitude” has led to many key discoveries and application of basic science knowledge in caring for patients. Some examples of important achievements by internists include: