Also known as an internist, an internal medicine physician is a medical specialist who is trained in the diagnosis, treatment, and prevention of adult diseases. Internists generally specialize in highly complex health situations and may be consulted by other doctors when presented with particularly challenging or puzzling cases. While internists often practice as primary care physicians, they are not to be confused with family physicians or general practitioners, whose training and scope of practice are distinctly different.
The internal medicine physician emerged as a specialty in late 19th century Germany. A literal translation from the German innere medizin, the term originally described the unique qualification of the internal medicine physician to combine the scientific principles of the laboratory with the day-to-day issues of clinical medicine. Internists were able to access medical and scientific techniques that were not available to general practitioners, and were often asked to consult when a patient required specialized treatment. The development of this new field of specialization addressed the needs of the physicians, who aspired to a higher degree of authority than the general practitioner, but wanted to avoid limiting their scope of practice to a single organ or system.
Today, the internal medicine physician treats adult patients almost exclusively, with an emphasis on whole patient and whole life care. An internist will act as a primary care physician but, unlike a general practitioner, will continue to be involved in patient care, even if the patient is transferred to a hospital, intensive care unit, or nursing home. In a clinical setting, internists will perform physicals, manage illnesses through diet and medication, and monitor patient health. In addition to the diagnosis and treatment of illnesses, internists tend to focus on general wellness issues, such as mental health and substance abuse.
When not working in a primary care capacity, an internal medicine physician may make rounds at a hospital or act as a specialist consultant. The internist is essentially an elite generalist, who is uniquely qualified to diagnose and treat complex patient issues that may be beyond the scope of a general practitioner or family doctor. Chronic illnesses or multiple disorders presenting in unison may pose any number of challenging issues that an internal medicine physician might be called on to treat.
Additionally, many internists choose to undergo fellowships to sub-specialize in a particular field. There are 13 areas of sub-specialty within the field of internal medicine, such as nephrology, cardiology, and pulmonology. While internists typically do not perform surgery, they are usually intimately involved in the diagnosis, treatment, and after-care of patients with conditions that may require surgical intervention. Often referred to as a 'doctor's doctor,' the internal medicine physician is a highly trained professional who is concerned with all aspects of patient health.