What Is an Allergist?

An allergist is a physician who is specially trained to help people who have allergies, asthma, and similar immunologic conditions. You may be referred to an allergist by your primary care doctor, for example, if your seasonal allergies cannot be tamed with standard treatments. Given their specific area of focus, allergists are often able to identify and help manage causes of severe or life-threatening symptoms.

Questions to Ask Your Potential Allergist

Theresa Chiechi / Verywell

Allergy and immunology is a combined specialty in which physicians train in both subspecialty areas. Practitioners in the United States are commonly referred to as allergist/immunologist. However, “allergist” and “immunologist” should not be used interchangeably; in some countries, providers are trained in only one of the two specialties. There are also older providers in the United States who have only been trained in one of the two specialties.


Allergists are trained to diagnose, treat, and manage allergies, which are conditions that cause the immune system to react abnormally to otherwise harmless substances.

These specialists also diagnose and treat conditions in which allergy plays a role (such as asthma), as well as other common and uncommon disorders associated with an abnormal immune response.

Depending on your diagnosis, you may only need to see an allergist for your medical care. But because allergies and asthma can complicate other conditions—such as COPD, migraine, and autoimmune diseases—it is not uncommon for allergists to work alongside pulmonologists, rheumatologists, dermatologists, and other medical specialists.

Allergists should not be confused with rheumatologists, who diagnose and treat autoimmune diseases (like lupus and rheumatoid arthritis) and chronic musculoskeletal diseases (like osteoarthritis).

Food and Drug Allergies

Allergies can be triggered by food (like peanuts or milk) and medications (like penicillin or sulfa drugs).

In some cases, the reaction may be a true allergy, in which the immune system directly reacts to an allergen. And an allergic reaction may occur due to cross-reactivity, meaning that food or drugs similar in structure to those involved in a true allergy trigger a reaction that's generally milder.

Hay Fever

Hay fever, also known as allergic rhinitis, is a common allergic condition that causes sneezing, runny nose, and red, itchy eyes.

Typically occurring in response to tree or grass pollens, hay fever is one of the most common chronic conditions seen by doctors, with no less than 7% of adults and children diagnosed with allergic rhinitis in the United States each year.


Asthma is a chronic lung disease that's characterized by inflammation and narrowing of the airways. Asthma causes episodes (called attacks), with symptoms of wheezing, chest tightness, shortness of breath, and coughing.

The exact cause of asthma is unknown, but it is thought that many factors—including allergies—increase the risk. In fact, allergies and asthma often occur together.

Chronic Sinusitis

Sinusitis, also known as rhinosinusitis, is a common condition in which the sinuses become inflamed, causing congestion, runny nose, and sinus headache.

The condition is considered chronic if it persists for 12 weeks or more. Acute sinusitis usually resolves within three weeks.


Hives, known by the medical term urticaria, are raised welts on the skin that develop in response to allergic and non-allergic triggers. The welts can vary in size and are often red and itchy.

Chronic idiopathic urticaria is a common form of urticaria in which symptoms are long-lasting and recurrent, and no known cause can be found.

It is estimated that between 15% and 23% of adults will experience at least one bout of urticaria in their lifetime.

Contact Dermatitis

Contact dermatitis is a condition in which physical exposure to an allergen or irritant causes local skin inflammation or a non-contagious rash.

If an allergy is involved, the condition is referred to as allergic contact dermatitis. Common allergens involved in allergic contact dermatitis include latex, nickel, dyes, and certain plants.


Eczema is the name for a group of conditions that cause patches of dry, red, itchy, and scaly skin. Atopic dermatitis is a form of eczema that usually develops during early childhood, but can occur at any age. Symptoms are chronic and often flare in acute episodes.

The cause of eczema is thought to be multifactorial; in most cases, it's caused by an overactive immune response to an irritant.

Primary Immunodeficiency

Primary immunodeficiency is a condition in which a person lacks an intact immune system and is less able to fight infection and disease. Unlike acquired immunodeficiency, such as that caused by HIV, primary immunodeficiency disease (PIDD) is generally something a person is born with.

There are over 300 diseases associated with PIDD, some of which mimic allergy, asthma, and eczema (or vice versa).


Anaphylaxis is a rare, sudden, and severe immune response to an allergen, most commonly a drug, food, or insect sting. While many allergic reactions consist of only local symptoms, anaphylaxis can affect the whole body.

If it's not treated, anaphylaxis can cause shock, coma, asphyxiation, respiratory or heart failure, and death.

If you think you may be experiencing anaphylaxis, do not wait for an appointment with an allergist. Call 911 or seek emergency care.

Some symptoms of anaphylaxis include:

  • Shortness of breath
  • Wheezing
  • Rapid or irregular heartbeat
  • Dizziness or lightheadedness
  • Confusion
  • Swelling of the face, tongue, or throat
  • A feeling of impending doom

Procedural Expertise

Allergists have many tools at their disposal to identify and treat the cause of your symptoms and to help you manage your condition so you feel your best.

Allergy Testing

An allergist may perform a variety of tests to confirm the presence of an allergy and pinpoint the type of allergens involved.

These include allergen tests. During these tests, tiny amounts of a variety of allergens are placed under the skin (called a skin test) or applied to the skin on an adhesive patch (called a patch test).

An allergist can also conduct blood tests that detect antibodies produced by the body in response to a specific allergen.


Spirometry is a common in-office test used to evaluate how well the lungs work. It involves a handheld instrument, called a spirometer, that measures the amount and force of air you can breathe in and out of your lungs. It can be used to diagnose asthma and other conditions that affect breathing.

Spirometry is also used by pulmonologists, who specialize in lung diseases. An allergist may work with a pulmonologist if a chronic lung condition, like COPD, is worsened by asthma or allergy.

Challenge Tests

One of the tools that allergists commonly use to diagnose allergies is a challenge test.

Bronchoprovocation challenge tests involve inhaling aerosolized chemicals or cold air, or performing exercises. These are done to see whether they induce asthma symptoms.

Oral food challenge tests involve eating tiny amounts of certain foods in slowly increasing amounts to see if they trigger food allergy symptoms.

Elimination Diets

Elimination diets take a similar approach to challenge testing, wherein suspected food allergens are excluded from a diet for three to six weeks. Thereafter, the various allergens are reintroduced one at a time into the diet in gradually increasing amounts to see if a reaction occurs.

Elimination diets can be used to confirm gluten intolerance, lactose intolerance, food sensitivity, or triggers of irritable bowel syndrome (IBS). Elimination diets can also be used in the treatment of eosinophilic esophagitis, another condition treated by allergists/immunologists.


There are many prescription and over-the-counter medicines used by allergists to relieve allergy and asthma symptoms

They include:


Immunotherapy is a treatment modality that trains your body to become less responsive to specific allergens. With controlled exposure to gradually increasing doses of an allergen, immunotherapy can desensitize an individual to an offending substance.

Immunotherapy can be given as a series of allergy shots or a series of drops placed under the tongue (sublingual immunotherapy).

Compared to allergy medicines, which cover up symptoms, immunotherapy aims to lower immune response so that you don't need as many medications; some people may even be able to get off of all allergy medications after completing immunotherapy.


There are no certified subspecialties for allergists/immunologists, but many choose to focus their practice on specific areas of interest.

Some may work with children or involve themselves exclusively in the field of immunology research. Others may decide to teach in an academic setting.

There are also formal career pathways and additional training available to allergists who want to expand the scope of their practice.

Board certification is currently available for:

  • Allergy/immunology and pediatric pulmonology
  • Allergy/immunology and pediatric rheumatology
  • Allergy/immunology and adult rheumatology

Training and Certification

From start to finish, an allergist/immunologist will undergo around nine years of additional training following a bachelor's degree.

After earning a 4-year medical degree, an allergist must complete a three-year residency in either internal medicine or pediatrics and then pass an exam from either the American Board of Internal Medicine or the American Board of Pediatrics.

Internists and pediatricians interested in becoming allergists must undergo two or more years of additional fellowship training. To be eligible for board certification, the fellowship program must be recognized and approved by the American Board of Allergy and Immunology (ABAI). Allergists listed as "ABAI-certified" have successfully passed the certifying exam of the ABAI.

To maintain certification, allergists must meet additional requirements. These include completing 25 continuing medical education credits every year. This demonstrates the allergist is up to date in their practices and knowledge.

Appointment Tips

If you need to find an allergist in your area, you can either ask your primary care doctor for a referral or find one using an online locator offered by the American Academy of Allergy, Asthma, and Immunology or the American College of Allergy, Asthma, and Immunology.

Among the questions you can ask an allergist you're considering working with:

  • How much of your practice is devoted to my condition? If you have an uncommon disorder, you will likely want someone with experience treating patients with that condition.
  • Will I see you or someone else in your office? For certain tests, procedures, and treatments, a nurse, nurse practitioner, or physician's assistant may be suited to oversee your care. But you might want to know when the allergist will be taking care of you.
  • How far in advance do I need to make appointments? This is especially important if your schedule is tight or you end up having to be seen in a timely manner. Ask under what conditions you can get a last-minute appointment.
  • When is your office open for allergy shots? If you need allergy shots, you'll be required to visit at least weekly for the first few months. If you work or have children, scheduling can sometimes be difficult. Ask if the clinic gives allergy shots during times when you can go in.
  • What insurance do you accept? It is always important to check that the doctor accepts your health insurance if you have it. This also includes labs or imaging facilities they use. If not, your care may not be covered, or your out-of-pocket costs may be excessive.

Before embarking on the diagnostic process or any treatment, ask:

  • What types of tests might be involved? Generally speaking, allergy tests are performed in stages, starting with blood tests and skin tests. If other investigations are recommended, such as imaging tests or pulmonary function tests, ask why.
  • How long will my appointment be? Certain allergy tests require the administration of an allergen to see if it's problematic for you. Allergy shots involve the same, but for treatment purposes. Since this could result in a reaction, your allergist will want to observe you for some time before letting you leave. It can be helpful to get a sense of the timeframe in case you have a commitment immediately after your appointment.
  • Who can I call in the event of an emergency? In the event of a true emergency, like an anaphylactic reaction, a call to 911 is warranted. Ask when it's better to call your allergist instead and what number you can call when the office is closed.
  • Can I call after-hours or on weekends? There may be non-emergency situations in which you need to call your allergist (such as questions about medications). Though many allergists offer after-hours call services, some bill for the calls. If so, ask what the charges are and check to see if they are covered by your insurance.

A Word From Verywell

Allergists have become increasingly important as the incidence of certain allergies continues to rise in the United States.

If working with an allergist, be sure that all reports and treatments are shared with your primary care physician and any other specialist you may be seeing.

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By Daniel More, MD
Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and currently practices at Central Coast Allergy and Asthma in Salinas, California.