Allergy/Immunology is a specialty of medicine which deals with diagnosis and treatment of asthma, allergies. An allergy is an abnormal reaction to a substance or environmental trigger. Doctors specializing in this field are called Allergists. Allergists determine what substances or triggers cause reactions in each individual and look for ways to treat those allergies, so the sufferer can go on to live a normal life. Allergists may perform allergy tests like skin challenge, scratch test, breathing test to make accurate diagnosis and provide the right treatment plan.

An internist or Internal Medicine doctor is someone who specializes in diagnosing and treating illnesses, diseases, and health problems. Most internists are also primary care doctors and treat patients on a regular basis. They can diagnose and treat common illnesses or more serious problems. Most people see an internist regularly. Those with chronic illnesses may do so on a monthly or even weekly basis. Internists are the most common types of doctors.