As medical knowledge has become greater, doctors have formed various specialties. In addition, other health professional fields have been created. Here is some information about physician specialists, and other specialists, and what they do.
Physicians that choose to train for a specialty complete additional training. After (typically) 4 years of medical school, they go on to internship and residency, which can take anywhere from 1-5 years (depending on the kind of residency training). Then, they go on for still more training in a specialty, which adds several more years.
After completing training in a specialty, physicians take examinations to become "board-certified" in their specialty. Many of these subspecialties have formal certification requirements. Those who have certificates in subspecialties (such as cardiology) were first certified in a specialty (such as internal medicine).
Provide psychiatric care for patients with alcohol, drug, or substance abuse problems and help with the emotional and behavioral consequences. Subspecialty of Psychiatry.
Treat the unique healthcare concerns of adolescents, including physical, psychological, and social issues. Subspecialty of Internal Medicine or Pediatrics.
Allergy and Immunology
Treat disorders of the immune system such as asthma, eczema, nasal allergies, food allergies, and immunodeficiency diseases.
Provide relief from acute and chronic pain and help stabilize a patient's condition during and after an operation or other medical procedure.
Blood Banking/Transfusion Medicine
Manage the safety and supply of a blood bank, supervise testing to ensure compatibility before blood transfusions, and prepare special blood components such as platelets for transfusion. Subspecialty of Pathology.
Manage technical procedures involved in evaluating heart rhythms and determining or providing appropriate treatment. Subspecialty of Cardiology.
Study the heart and treat disorders of the heart and blood vessels.
Diagnose and treat diseases of the heart, lungs, and blood vessels and manage cardiac conditions such as heart attacks. Subspecialty of Internal Medicine.
Analyze the biochemistry of the body as it pertains to the detection or monitoring of a disease. Subspecialty of Pathology.
Child and Adolescent Psychiatry
Diagnose and treat children and adolescents with mental, addictive, or emotional disorders. Subspecialty of Psychiatry.
Clinical Biochemical Genetics
Perform and interpret biochemical analysis in connection with the diagnosis and treatment of genetic diseases. Subspecialty of Medical Genetics.
Perform and interpret laboratory analysis of cellular structures, mainly chromosomes. Subspecialty of Medical Genetics.
Diagnose and treat a wide range of genetic disorders, interpret family health histories, perform specialized laboratory procedures, and provide health care. Subspecialty of Medical Genetics.
Clinical and Laboratory Immunology
Use laboratory tests and procedures to diagnose and treat disorders of the immune system. Subspecialty of Allergy and Immunology, Internal Medicine, or Pediatrics.
Clinical and Laboratory Dermatological Immunology
Diagnose and treat skin diseases that involve the immune system. Subspecialty of Dermatology.
Clinical Molecular Genetics
Perform and interpret molecular laboratory analyses in connection with genetic diseases. Subspecialty of Medical Genetics.
Diagnose and treat disorders of the nervous system and muscles using techniques that measure electrical forces in the body. Subspecialty of Neurology or Psychiatry.
Colon and Rectal Surgery
Diagnose and treat diseases of the intestinal tract, colon, rectum, anal canal, and perianal area.
Critical Care Medicine
Diagnose and treat patients with multiple organ dysfunction or life-threatening disorders such as shock, coma, heart failure, and respiratory arrest, primarily in intensive care or critical care units. Subspecialty of Anesthesiology, Internal Medicine, or Obstetrics and Gynecology.
Diagnose disease by studying cells obtained from body secretions, scrapings, or aspiration, often to look for evidence of cancer. Subspecialty of Pathology.
Diagnose and treat disorders of the skin, mouth, external genitalia, hair, and nails, such as skin cancers, moles, allergic disorders, and scarring.
Diagnose and monitor diseases of the skin by examining and evaluating tissue specimens from patients. Subspecialty of Dermatology or Pathology.
Diagnose disease using imaging techniques such as x-rays and ultrasound. Subspecialty of Radiology.
Endocrinology, Diabetes, and Metabolism
Diagnose and treat disorders of the endocrine system such as thyroid and adrenal gland problems and disorders such as diabetes, pituitary diseases, and menstrual and sexual problems. Subspecialty of Internal Medicine.
Make immediate decisions and take action to prevent death or disability in an acutely ill or injured person, usually in a hospital emergency department.
Prevent, diagnose, and treat a wide variety of ailments in patients of all ages, incorporating training in surgery, psychiatry, internal medicine, obstetrics and gynecology, pediatrics, and geriatrics.
Investigate and evaluate cases of sudden, unexpected, and suspicious deaths; includes coroners and medical examiners. Subspecialty of Pathology.
Diagnose and treat problems of the stomach, pancreas, intestines, liver, and gallbladder, such as abdominal pain, ulcers, cancer, and jaundice. Subspecialty of Internal Medicine.
General Vascular Surgery
Surgically treat disorders of blood vessels. Subspecialty of Surgery.
Diagnose and treat disorders common in older people. Subspecialty of Family Practice or Internal Medicine.
Diagnose and treat the mental, addictive, and emotional disorders of the elderly. Subspecialty of Psychiatry.
Diagnose and treat patients with cancer occurring in the female reproductive organs. Subspecialty of Obstetrics and Gynecology.
Diagnose and treat, sometimes by performing surgery, all structures that affect the form and use of the hand and wrist. Subspecialty of Orthopedic Surgery or Plastic Surgery.
Diagnose and treat diseases of the blood, spleen, and lymph glands, such as anemia, sickle cell disease, hemophilia, and leukemia. Subspecialty of Internal Medicine or Pathology.
Stand in for primary care doctors, when their patients are in the hospital. (Some primary care doctors take care of their patients in their offices, and also in the hospital, when the patients need to be hospitalized. When hospitalists care for a hospitalized patient, they remain in close touch with the patient's primary care doctor.)
Study the cause and prognosis of disease by examining the immunological status of tissues. Subspecialty of Pathology.
Diagnose and treat infectious diseases and practice preventive medicine. Subspecialty of Internal Medicine.
Provide long-term comprehensive care, manage common illnesses and problems of adolescents and adults, treat mental health and substance abuse problems, and educate patients on disease prevention and wellness.
Diagnose and treat patients who have committed a crime and advise on compensation cases and commitment of the mentally ill. Subspecialty of Psychiatry.
Maternal and Fetal Medicine
Diagnose and treat patients with complications during or caused by pregnancy. Subspecialty of Obstetrics and Gynecology.
Diagnose and treat patients with genetic-linked diseases and provide genetic counseling.
Isolate and identify agents that can cause disease such as viruses, bacteria, fungi, and parasites that are found in specimens from patients. Subspecialty of Pathology.
Provide care for sick newborn infants, often as a consultant to pediatricians. Subspecialty of Pediatrics.
Diagnose and treat disorders of the kidneys, high blood pressure, and fluid and mineral imbalances. Subspecialty of Internal Medicine.
Diagnose and surgically treat problems of the nervous system (including the brain, spinal cord, and nerves) and the blood vessels and structures that support that system.
Diagnose and treat all disorders of the nervous system, including the brain, spinal cord, nerves, and the structures that support them.
Diagnose diseases by examining tissues from the nervous system and skeletal muscles, primarily as consultants to neurologists and neurosurgeons. Subspecialty of Pathology.
Diagnose disorders of the brain, spine, spinal cord, head, and neck using radiology imaging procedures. Subspecialty of Radiology.
Diagnose and treat diseases using radioactive materials called radionuclides, using images of the body taken by means of positron emission tomography (PET) and single photon emission computed tomography (SPECT) scans. Subspecialty of Radiology.
Obstetrics and Gynecology
Diagnose and treat disorders and conditions of the female reproductive system, including pregnancy.
Diagnose and treat all types of cancer, often with chemotherapy, and consult with radiologists and surgeons on other treatments. Subspecialty of Internal Medicine.
Diagnose and treat problems related to the eyes and vision, including vision correction with glasses or contact lenses and treatment of diseases such as glaucoma.
Diagnose and treat problems related to the form and function of the muscles and bones of the arms, legs, shoulders, hips, and spine, including disorders present at birth, injuries, and infections.
Diagnose and treat diseases of the ear and the surrounding bones, including problems with hearing and balance. Subspecialty of Otolaryngology.
Diagnose and treat diseases, including cancer, that affect the ears, respiratory system, and head and neck. Has expertise in plastic and reconstructive surgery.
Treat people experiencing acute and chronic pain. Subspecialty of Anesthesiology.
Explore the causes and nature of diseases through examining body tissues and fluids, using microscopic examination and other laboratory tests.
Diagnose and treat infants and children who have problems of the heart and blood vessels. Subspecialty of Pediatrics.
Pediatric Critical Care Medicine
Treat infants and children needing advanced life support and coordinate the care and treatment provided by other involved physicians. Subspecialty of Pediatrics.
Pediatric Emergency Medicine
Treat emergencies in infants and children. Subspecialty of Emergency Medicine or Pediatrics.
Diagnose and treat infants and children who have diseases or disorders such as diabetes mellitus, growth problems, early or late puberty, and birth defects resulting from problems in the hormonal system. Subspecialty of Pediatrics.
Diagnose and treat disorders occurring in the digestive tract of infants and children. Subspecialty of Pediatrics.
Diagnose and treat infants and children who have blood disorders, cancer, or both. Subspecialty of Pediatrics.
Pediatric Infectious Disease
Diagnose and treat infants and children who have infectious diseases such as acquired immunodeficiency syndrome (AIDS) or tuberculosis that are more complicated than normal childhood illnesses. Subspecialty of Pediatrics.
Diagnose and treat infants and children who have problems associated with the kidneys and urinary tract. Subspecialty of Pediatrics.
Diagnose and treat infants and children with disorders of the ear, respiratory system, and head and neck, including problems with speech and hearing. Subspecialty of Otolaryngology.
Diagnose, using laboratory analysis of diseased tissue and body fluids, diseases that occur during fetal growth, infancy, and childhood. Subspecialty of Pathology.
Diagnose and treat respiratory diseases in infants and children. Subspecialty of Pediatrics.
Use imaging procedures such as x-rays to diagnose and treat diseases in infants and children. Subspecialty of Radiology.
Diagnose and treat rheumatological diseases of the joints, muscles, tendons, and bones such as arthritis and muscle strains in infants and children. Subspecialty of Pediatrics.
Surgically treat diseases and disorders of infants and children. Subspecialty of Surgery.
Provide a broad spectrum of health care for children from infancy to young adulthood, including physical, emotional, and social health; provide preventive health care; and treat disease.
Physical Medicine and Rehabilitation
Diagnose and treat impairments or disabilities involving muscles, nerves, and other body systems, focusing on restoration of physical, psychological, social, and vocational function.
Repair or reconstruct parts of the body, including the face, hands, breasts, and trunk.
Focuses on the preventive care (for example, for diabetics) and treatment of the feet and legs. Podiatrists are doctors that receive four years of training and are licensed to independently diagnose and treat (both medically and surgically) conditions of the feet and legs.
Focus on the health of individuals and groups to maintain health and prevent disease, disability, or premature death; may work in public health agencies and large health care systems or with employee groups.
Diagnose and treat mental, addictive, and emotional disorders such as depression, anxiety disorders, substance abuse, sexual dysfunction, stress, and developmental problems; order diagnostic laboratory tests; and prescribe medications.
Pulmonary Disease (Pulmonology)
Diagnose and treat diseases of the lungs and airways such as lung cancer, pneumonia, pleurisy, asthma, sleep disorders (which often affect breathing), and emphysema. Subspecialty of Internal Medicine.
Treat diseases such as malignant tumors with radiation. Subspecialty of Radiology.
Diagnose using radiology methods, such as x-rays, ultrasound, and nuclear medicine, or treat disease using radiation.
Diagnose and treat complex problems related to hormonal aspects of the reproductive system, especially fertility problems.
Diagnose and treat diseases of joints, muscles, bones, and tendons such as arthritis, back pain, and common athletic injuries. Subspecialty of Internal Medicine.
Promote wellness, health, fitness, and the prevention of injuries using exercise physiology, nutrition, psychology, and physical rehabilitation. Subspecialty of Emergency Medicine, Family Practice, Internal Medicine, or Pediatrics.
Surgically treat all areas of the body and provide care before, during, and after surgery.
Surgical Critical Care
Treat critically ill people, including injury victims and those who have had surgery, in the emergency department, burn unit, and intensive care unit. Subspecialty of Surgery.
Surgically treat patients with disorders of the chest such as coronary artery disease, lung cancer, and chest tumors.
Treat people who have been poisoned by household or industrial toxins, environmental toxins, and prescription and nonprescription drugs. Subspecialty of Emergency Medicine, Pediatrics, or Preventive Medicine.
Diagnose and treat disorders, such as decompression illness and diving injuries, caused by lower- or higher-than-normal barometric pressures. Subspecialty of Preventive Medicine.
Diagnose and treat disorders of the urinary tract in men and women and the genital tract in men.
Vascular and Interventional Radiology
Diagnose and treat disease by placing an instrument into an organ or blood vessel, guided by radiologic imaging procedures such as ultrasound and magnetic resonance imaging (MRI). Subspecialty of Radiology.
Other Healthcare Specialists
Other healthcare specialists who are not doctors work with doctors in the care of patients. They all receive special training, take examinations, and receive certification in their professions.
Emergency Medical Technicians (EMTs)
Provide emergency care and transport seriously ill people to hospitals. Various levels of training, with the most highly trained being called paramedics.
Home Health Aides
Perform personal services such as cooking, housekeeping, or help with bathing for homebound people.
Licensed Practical Nurses (LPNs)
Provide nursing care under the supervision of registered nurses.
Perform laboratory tests.
Nurses who receive special additional training to perform physical examinations, make diagnoses, and prescribe treatment, often under the supervision of a physician.
Help patients learn the skills needed for daily activities.
Fit people with glasses and contact lenses.
Measure vision and prescribe corrective lenses.
Orthotists and Prosthetists
Fit braces and artificial limbs.
The most highly trained emergency medical technicians (EMTs): provide emergency care for people who have accidents or life-threatening medical emergencies outside of the hospital.
Mix and dispense medications.
Work to prevent patients loss of function and to restore function.
Receive special training to perform physical examinations, make diagnoses, and prescribe treatment, under the supervision of a physician.
Diagnose and treat mental health problems.
Take and develop x-rays.
Help patients with matters such as finances, insurance, and family problems.
Measure and treat speech disorders.
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.