Allergists are doctors who treat hay fever and other allergies, asthma, and diseases of the immune system. They are also called immunologists.

An allergy is a response by the immune system to substances in the environment. To diagnose allergies, allergists and immunologists ask about symptoms, family history, home, work, and school environments.

During an exam, allergists and immunologists examine the upper and lower respiratory system. They look at the nose, the mouth, the ears, and the eyes. They feel the lymph nodes in the neck and listen to the heart and lungs.

Allergists and immunologists may order several types of tests such as:

• Skin tests
• Blood tests
• Breathing tests

They review test results and develop a treatment plan for each patient. They may suggest environmental changes, such as limiting exposure to pets for someone who is allergic to animals. They also prescribe drugs to relieve the symptoms. Allergists and immunologists keep detailed patient records.

Some allergists and immunologists work with people whose immune system attacks the body unnecessarily. When a patient has an organ transplant, an allergist or immunologist is on the medical team to manage the reaction until the new organ is accepted by the body.

Many allergists and immunologists work at medical offices or hospital clinics. Others are involved in research at medical schools, government agencies, or drug companies. Some allergists and immunologists combine patient care with teaching and research.