An allergist (also called an allergist-immunologist) is the specialist who most commonly performs allergy testing. These doctors complete medical school, a residency in either internal medicine or pediatrics, and then a two-year fellowship focused entirely on allergies and the immune system. They are the go-to for skin prick tests, blood allergy panels, and oral food challenges. That said, they aren’t the only doctors who test for allergies. Depending on your symptoms, a dermatologist or an ENT (ear, nose, and throat doctor) may also run specific types of allergy tests.
Allergists: The Primary Allergy Specialists
Board-certified allergists complete 24 continuous months of fellowship training in allergy and immunology after their initial residency. That training covers the full range of allergic conditions: seasonal and environmental allergies, food allergies, drug allergies, insect sting reactions, asthma, and immune system disorders. The American Board of Allergy and Immunology certifies these specialists, and you can verify any allergist’s certification status through the board’s website.
An allergist’s office is typically equipped to perform all the major forms of allergy testing in a single visit and to handle allergic reactions if they occur during testing. This is especially important for procedures like oral food challenges, where you eat small, gradually increasing amounts of a suspected food allergen while being monitored. That process takes about four hours, including at least two hours of observation after the last dose. This kind of supervised challenge requires trained staff and emergency treatment on hand, which is why it’s done in a specialist’s office rather than a primary care clinic.
Types of Tests Allergists Perform
The most common test is the skin prick (or scratch) test. A thin needle pricks the skin on your forearm or back with tiny amounts of potential allergens, or droplets are placed on the skin and lightly scratched in. Reactions like redness or raised bumps called wheals typically appear within 15 minutes. This test covers airborne allergies, food allergies, and penicillin allergies.
If your skin prick results come back negative or unclear, the next step is often an intradermal skin test. Small amounts of an allergen are injected just under the outer layer of skin. This more sensitive method is commonly used to check for reactions to airborne irritants, medications, and insect stings.
Blood tests are the other major option. A lab measures levels of an antibody called IgE in your blood sample. A total IgE test checks overall antibody levels, while a specific IgE test measures your response to one allergen at a time. Blood tests are useful when skin testing isn’t practical, for example if you can’t stop taking antihistamines or have a skin condition that would interfere with reading results. Your primary care doctor can order a blood allergy test, but an allergist is better positioned to interpret the results in context.
When a Dermatologist Does the Testing
If your main symptom is a persistent, itchy rash rather than sneezing or swelling, a dermatologist may be the right doctor to see. Dermatologists specialize in patch testing, which identifies contact allergies: reactions caused by substances that touch your skin, like metals, fragrances, preservatives, or chemicals you encounter at work.
Patch testing works differently from skin prick tests. Your dermatologist places small amounts of suspected allergens on your skin, covers each one with a patch, and you leave the patches on for 48 hours before returning to have them read. Not every dermatologist offers patch testing in their office, so you may be referred to one who does. If the first round doesn’t identify the cause, expanded patch testing is available for specific industries (florists, dental technicians, and others who handle particular chemicals daily). Expanded testing finds about 80% of allergens that standard panels miss.
ENT Doctors and Allergy Testing
Ear, nose, and throat specialists sometimes perform allergy testing when your symptoms overlap with conditions they already treat, like chronic sinusitis, nasal polyps, or recurring ear infections. If an ENT suspects that underlying allergies are driving your sinus problems, they may run skin prick tests or blood panels in their own office rather than sending you to a separate allergist. This can streamline care when you’re already being treated for a structural or chronic issue in the sinuses or airways.
What Your Primary Care Doctor Can Do
Most general practitioners and family doctors don’t perform skin testing in their offices, but they can order blood-based allergy panels. This is often the first step before a referral. If your blood results suggest significant allergies or your symptoms are complex, your primary care doctor will typically refer you to an allergist for more precise skin testing and a treatment plan. For straightforward seasonal allergies that respond well to over-the-counter medications, a referral may not be necessary at all.
How to Prepare for Allergy Testing
If you’re scheduled for skin testing, the most important preparation is stopping antihistamines ahead of time. Many guidelines say three to four days is enough, but a significant number of patients still have suppressed skin reactions at that point. For the most accurate results, stop most antihistamines at least seven days before your appointment. Diphenhydramine (Benadryl) clears faster and only needs to be stopped 48 hours beforehand. Hydroxyzine (Atarax) takes longer and should be stopped 10 days prior.
If you take beta-blockers for blood pressure or heart conditions, those should ideally be stopped five to seven days before testing as well, though you’ll need to coordinate that with the prescribing doctor. Blood-based allergy tests don’t require you to stop any medications, which is one reason they’re sometimes chosen instead of skin testing.
Choosing the Right Doctor for Your Symptoms
Your symptoms point toward the right specialist. Sneezing, itchy eyes, hives, food reactions, or asthma flare-ups all fall squarely in an allergist’s territory. A rash that keeps coming back in the same spot, especially if it seems connected to jewelry, cosmetics, or something you touch regularly, is better suited for a dermatologist’s patch testing. Chronic sinus congestion or recurring infections that haven’t responded to standard treatment could warrant an ENT who also tests for allergies.
If you’re unsure where to start, a visit to your primary care doctor for a blood panel can help narrow things down and guide the referral. You can also verify an allergist’s board certification through the American Board of Allergy and Immunology’s online tool before booking an appointment.