Overview
Allergy and immunology is a branch of medicine that studies the immune system and treats allergic diseases and certain immune disorders. Common problems seen in this specialty include allergic rhinitis, asthma, eczema, hives, food allergy, insect sting allergy, and drug allergy. Some people are also evaluated for recurrent infections or suspected immune deficiency.
Key Symptoms
Allergy symptoms depend on what part of the body is affected. They may include sneezing, itchy or runny nose, red or itchy eyes, cough, wheeze, shortness of breath, rash, hives, swelling, vomiting, diarrhea, or stomach pain. In severe reactions, symptoms can include throat tightness, trouble breathing, dizziness, or collapse.
Causes and Risk Factors
Allergic conditions happen when the immune system reacts to triggers such as pollen, dust mites, animal dander, mold, foods, medicines, or insect stings. Family history, asthma, eczema, and other allergic conditions can raise the chance of developing allergies. Environmental exposures and repeated contact with triggers may also play a role.
Who Is Affected
Allergic conditions can affect people of any age, from infancy through older adulthood. Some problems, such as eczema and food allergy, often begin in childhood, while others may appear later in life. Immune system disorders can also affect people across age groups and may be inherited or acquired.
Prevention
Prevention focuses on reducing exposure to known triggers and having a clear care plan. This may include controlling indoor allergens, reading food labels carefully, avoiding medicines that previously caused reactions, and reducing exposure to smoke or air pollution when possible. People with severe allergies may be advised by their clinician to carry emergency medication and wear medical identification.
Diagnosis and Tests
Diagnosis usually begins with a detailed history of symptoms, timing, suspected triggers, home and work exposures, and past reactions. Depending on the concern, testing may include skin prick testing, blood tests for allergy-related antibodies, lung function testing, patch testing, or supervised food or drug challenge testing. Test results are interpreted together with the history because a positive test alone does not always mean a person has a true allergy.
Treatment Categories
Treatment depends on the condition and may include trigger avoidance, symptom-relieving medicines, anti-inflammatory treatments, inhaled therapies for asthma, skin care plans for eczema, or immunotherapy such as allergy shots or tablets for selected patients. Some people with severe or whole-body reactions need an emergency action plan. People with immune disorders may need a different type of evaluation and treatment from those with allergies.
Living With It
Living with allergies or immune conditions often involves learning to recognize symptoms early and manage triggers at home, school, work, and during travel. Written action plans can help families and caregivers respond consistently. Follow-up visits are important when symptoms change, reactions become more severe, or treatment is not working well.
When to Seek Medical Care
Seek medical care if symptoms keep returning, interfere with sleep or daily activities, involve wheezing or repeated coughing, or happen after eating, taking medicine, or an insect sting. Medical review is also important for frequent infections, poor growth in a child, or reactions that are hard to explain. New or worsening symptoms should be discussed with a healthcare professional.
When It May Be an Emergency
Get emergency help right away for trouble breathing, throat tightness, swelling of the tongue, fainting, severe dizziness, blue lips, or a rapidly spreading reaction after a food, medicine, or insect sting. These can be signs of anaphylaxis, a severe allergic reaction that needs urgent treatment. If emergency medication has been prescribed, use it as instructed and then seek emergency care.