What to Expect at Your Allergist Appointment

What an allergist does and why you're going

An allergist is a doctor who diagnoses and treats allergic reactions, asthma triggered by allergens, and immune system responses to substances that don't bother most people. You might see an allergist because you have seasonal allergies (hay fever), year-round sneezing and congestion, hives or skin reactions, food allergies, pet allergies, or asthma that gets worse at certain times of year or around specific triggers.

Unlike your primary care doctor, an allergist has extra training in how the immune system reacts to allergens and how to test for them. They can run specific tests to identify exactly what you're allergic to, and they can prescribe or recommend treatments tailored to your particular triggers. Many allergists also offer immunotherapy — allergy shots or sublingual tablets — which can reduce your symptoms over time by gradually desensitizing your immune system.

Key Takeaways

• Bring a list of your symptoms, when they happen, and what makes them better or worse, because the allergist will ask detailed questions about your medical history.
• Allergy testing usually involves small pricks or scratches on your skin or a blood test, and you'll get results the same day for skin tests.
• Stop taking antihistamines (like Benadryl or Claritin) for three to seven days before your appointment if you're having a skin test, because they block the test from working.
• Your appointment will likely last 30 to 60 minutes, and you should plan to stay longer if testing is involved.
• The allergist will discuss treatment options with you, which may include avoiding triggers, over-the-counter medications, prescription medications, or immunotherapy.

What to bring and how to prepare

Bring your insurance card and photo ID, just as you would for any doctor's visit. If this is your first appointment with this allergist, arrive 10 to 15 minutes early to fill out intake paperwork. The form will ask about your medical history, current medications, family history of allergies, and your symptoms.

Write down your symptoms before you go. Note when they happen (morning, evening, certain seasons), what they feel like (itching, congestion, wheezing, hives), and what seems to trigger them or make them worse. If you suspect a food allergy, write down what you ate and what happened. If you think it's a pet or pollen, note when you're around those things and how you feel. This detail helps the allergist narrow down what to test for.

If you're scheduled for allergy skin testing, stop taking antihistamines three to seven days before your appointment. This includes over-the-counter medications like Claritin, Allegra, Benadryl, and Zyrtec, as well as some prescription antihistamines. These drugs suppress the allergic reaction that the test relies on, so they'll make the test unreliable. Ask your allergist's office which medications to pause — some decongestants and other drugs can also interfere. If you're on a medication you're unsure about, call ahead and ask.

How allergy testing works

The allergist will likely offer one of two types of testing: a skin test or a blood test. Skin testing is faster and usually happens during your appointment. The allergist or a nurse will prick or scratch your skin — usually on your forearm or back — with a tiny amount of different allergen extracts. Each prick is labeled, so the doctor knows which allergen is which. You'll wait 15 to 20 minutes, and if you're allergic to something, a small raised bump (called a wheal) will appear at that spot. The bigger the bump, the stronger your reaction. You'll see your results before you leave.

A blood test (sometimes called a RAST or ImmunoCAP test) takes a sample to a lab and measures antibodies to specific allergens. This test doesn't require you to stop antihistamines, and it's useful if you have severe skin reactions, are on medications you can't pause, or have extensive eczema. Results usually come back in a few days to a week.

Some allergists also perform a challenge test, where you're exposed to a small amount of a suspected allergen (usually a food) under medical supervision to see if you react. This happens in the office where staff can treat any reaction immediately. Challenge tests are less common and usually only done when skin and blood tests are unclear.

What happens during your visit

The allergist will start by asking you questions about your symptoms, when they started, and what makes them better or worse. They'll ask about your family history — allergies often run in families — and whether you have asthma or eczema. They'll examine you, listening to your lungs if asthma is a concern and looking at your skin if you have rashes or hives.

Then comes testing, if that's part of your appointment. If you're having a skin test, the pricks are quick and usually cause only mild discomfort — more of a tickle than a sting. You'll sit in the waiting area while the test develops. If you're having a blood test, a phlebotomist will draw a small sample from your arm, which takes a few minutes.

After testing, the allergist will review your results with you and explain what you're allergic to and how severe each allergy is. They'll discuss what triggers your symptoms and talk through ways to avoid those triggers. Then they'll go over treatment options, which might include over-the-counter antihistamines or decongestants, prescription nasal sprays, inhaled corticosteroids for asthma, or immunotherapy if your allergies are severe or don't respond well to medication.

Understanding your test results

Skin test results are immediate and visual — you can see the bumps yourself. The allergist will measure each one and compare it to a control (a bump that should appear on everyone to show the test worked). A larger bump means a stronger allergic reaction. However, a positive test doesn't always mean you'll have symptoms when you encounter that allergen in real life. Some people test positive but don't react, and some have mild reactions. The allergist will correlate your test results with your symptoms to figure out which allergens are actually causing your problems.

Blood test results come back as numbers that show how much antibody your immune system is making to each allergen. Higher numbers mean a stronger allergic response. Like skin tests, a positive blood test result means your immune system reacts to that allergen, but it doesn't predict how severe your real-world symptoms will be.

The allergist will explain which results matter for your situation. You might test positive to something you're never actually exposed to, so the allergist helps you focus on the allergens that are actually affecting your daily life.

Treatment options the allergist may recommend

If your allergies are mild and seasonal, the allergist might suggest over-the-counter antihistamines (like Claritin or Allegra) or decongestants, taken during allergy season. If you have year-round symptoms or they're more severe, a prescription nasal spray with a corticosteroid (like Fluticasone or Mometasone) often works better than oral medications because it targets the nose directly.

For asthma triggered by allergens, the allergist may prescribe an inhaler — either a rescue inhaler for sudden symptoms or a daily controller inhaler to prevent symptoms. If you have food allergies, the allergist will discuss avoidance strategies and may prescribe an epinephrine auto-injector (EpiPen) if your allergy is severe.

If your symptoms don't improve with medication or you want a longer-term solution, the allergist may recommend immunotherapy. Allergy shots (subcutaneous immunotherapy) involve weekly injections of gradually increasing doses of allergen extract over three to five years. Sublingual tablets (like Oralair for grass pollen or Palforzia for peanuts) dissolve under your tongue daily. Both work by slowly training your immune system to tolerate the allergen. Immunotherapy takes months to show results but can significantly reduce symptoms or eliminate them entirely.

After your appointment

If the allergist prescribed medication, ask the pharmacist to explain how to use it — nasal sprays, inhalers, and other allergy drugs have specific techniques that affect how well they work. If you're starting immunotherapy, you'll have follow-up appointments to receive injections or pick up tablets, and the allergist will monitor how you're responding.

Keep track of your symptoms after starting treatment. If a medication isn't helping or causes side effects, call the allergist's office. They can adjust your treatment plan. If you had skin testing, keep the results or ask for a copy — they're useful to have if you see a different doctor later or if you need to explain your allergies to a school or employer.

Many allergists schedule follow-up visits every few months during the first year to see how you're doing and adjust treatment as needed. After that, you might see them once a year or only when your symptoms change.

Frequently Asked Questions

Can I eat before my allergy appointment?

Yes, you can eat normally. However, if you're having a skin test and suspect a food allergy, avoid eating that food for a few hours before the test so you don't trigger a reaction during testing. Ask your allergist's office if there are any specific food restrictions for your appointment.

What if I have a severe reaction during skin testing?

Severe reactions during skin testing are rare because only tiny amounts of allergen are used. The allergist's office is equipped to treat any reaction immediately with antihistamines or epinephrine if needed. Tell the staff right away if you feel dizzy, have trouble breathing, or develop hives beyond the test area.

How long does it take to see results from allergy shots?

Most people start noticing improvement after three to six months of allergy shots, though it can take up to a year to see the full benefit. The shots work gradually by desensitizing your immune system, so patience is important. Your allergist will monitor your progress at each visit.

Can I still take my regular medications before my appointment?

Most regular medications are fine, but antihistamines and some other drugs interfere with skin testing. Call your allergist's office with a list of everything you take — they'll tell you what to pause and for how long. Never stop a prescription medication without asking first.

What if my allergies are to something I can't avoid, like pollen?

That's exactly what allergy treatment is for. Medication can control your symptoms, and immunotherapy can reduce your sensitivity over time. Your allergist will help you manage unavoidable allergens through a combination of medication, environmental controls (like keeping windows closed during high pollen days), and sometimes immunotherapy.