Internal medicine or general medicine is the medical specialty dealing with the prevention, diagnosis, and treatment of adult diseases. It is the management of patients who have undifferentiated or multi-system disease processes. The specialty of internal medicine covers a wide range of conditions affecting the internal organs of the body - the heart, the lungs, the liver and gastro-intestinal tract, the kidneys and urinary tract, the brain, spinal column, nerves, muscles and joints.