Internal medicine or general medicine is the medical specialty dealing with the prevention, diagnosis, and treatment of adult diseases. Physicians specializing in internal medicine are sometimes referred to as internists. An internist is a personal physician who provides long-term, comprehensive care in the office and in the hospital, managing both common and complex illnesses of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and the digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

Emergency medicine is the medical practice concerned with caring for undifferentiated, unscheduled patients with illnesses or injuries requiring immediate medical attention. The practice of emergency medicine includes the initial evaluation, diagnosis, treatment, coordination of care among multiple providers and disposition of any patient requiring expeditious medical, surgical or psychiatric care.