An allergist specializes in the diagnosis and treatment of allergic diseases including asthma. An allergic disease results with the immune system that normally protects the body from harmful invaders such as viruses or bacteria , incorrectly recognizes a harmless substance such as pollen as a target for the immune system to attack. The reaction can produce undesirable and sometimes, life-threatening symptoms. To train as an allergist a physician who has completed an internal medicine or pediatric fellowship completes 3 years of additional training to identify the factors that initiate allergic diseases, and help patients to prevent or treat these conditions. Cardiovascular Disease - To become a cardiologist, a physician trained in internal medicine completes 4 to 5 years of additional training.
Cardiologists specialize in diseases of the heart and vascular system .
Cardiologists treat heart attacks, heart failure, and abnormal heart rhythms. They perform heart catheterization by which a catheter is inserted into a blood vessel going to the heart, in order to obtain information about the heart and the arteries supplying it. They also perform balloon angioplasty as a treatment for narrowed arteries in which a balloon-tipped catheter is inserted into an artery, usually the ones supplying the heart, to widen the vessel wall, thus increasing blood flow to a given area. After evaluation, they decide if heart surgery or other surgical procedures are needed. Endocrinology - To become an endocrinologist, a physician trained in internal medicine completes 2 to 3 years of additional training in the diagnosis and treatment of diseases associated with internal glandular secretions or hormones.