If you suffer from a runny nose, sneezing, or red, watery eyes, you may have allergies. But how do you know for sure? And how do you find out exactly what you’re allergic to?
Donatella Graffino, MD, an allergist and immunologist with Atlantic Health System, explains how to identify allergies, the different types of allergens, how to get diagnosed and what treatment options are available to you.
What are allergies?
Allergies are an overactive immune system response to an allergen. An allergen is a peptide, or piece of a protein, that the body doesn’t recognize. Allergens cause some sensitivity that produces a negative reaction in the body.
There are different allergy types, each causing different symptoms:
- Airborne allergies such as pollen, dust and pet dander are breathed in through the air. These are usually seasonal.
- Food and other ingestible allergies are from things you swallow and digest. They can also be injected, as in the case with some medications.
- Topical allergies, or skin allergies (called contact dermatitis), are caused by direct contact with various substances found in chemicals and everyday products ranging from cleaning supplies to cosmetics to jewelry.
“Allergies are very common,” says Dr. Graffino. "Between 30-40% of people have some level of allergy, and everyone is different with different triggers and different reactions.”
Many allergies are genetic, meaning they are passed down from generation to generation. If you are genetically predisposed to an allergen, it takes more than one exposure to cause a reaction. With the first exposure, you might become sensitized to that allergen. With a second exposure, you develop symptoms.
“Developing an allergy takes some time,” Dr. Graffino explains. “More than one exposure might be necessary to develop an allergy.”
Common allergens
Just like there are different types of allergies, there are different allergens, or triggers. Some common allergens include:
- Pollen (tree, ragweed, etc.)
- Pet dander
- Mold
- Milk
- Eggs
- Wheat
- Soy
- Peanuts
- Fish/shellfish (shrimp, lobster, crab, etc.)
- Tree nuts (almonds, cashews, walnuts, etc.)
- Bee venom
- Metals (nickel, cobalt, copper, etc.)
- Latex
- Penicillin and other medicines
Dr. Graffino says allergies can develop at almost any age, though less likely after age 70. You can also grow out of an allergy.
“About 85-90% of children with “Big 5” food allergies — milk, wheat, soy, egg, but NOT peanut — often grow out of them, with peanut being the one exception. Peanut allergies can be outgrown, but only 20-30% of the time” she says. “And while seniors are less likely to develop airborne allergies for the first time, they can still develop an allergy to certain medications.”
How do I know what I’m allergic to?
Watching for symptoms is the first clue to discovering an allergy. However, everyone is different, so how you react to an allergen may also vary.
Airborne allergies typically affect the respiratory tract. Symptoms are often red, puffy eyes, stuffy or runny nose, itchy throat and cough. “It feels like a bad cold that goes on for weeks, but without a fever,” Dr. Graffino explains.
Topical allergies produce a rash where the product or chemical came in contact with your skin. For example, if you have a nickel allergy, you may develop a rash behind your ears if your earring backs are made of nickel rather than another metal or plastic.
Food allergies cause a range of symptoms, depending on your level of sensitivity — from an itchy mouth and tingling lips to swelling and hives to anaphylaxis (a severe allergic reaction that makes it difficult to breathe). Gastrointestinal distress is also common (think nausea, vomiting, cramping and diarrhea).
If you think you’re allergic to something, talk to your primary care physician or an allergy specialist for a full evaluation and diagnosis.
How do doctors diagnose an allergy?
According to Dr. Graffino, the first step to diagnosis is to understand the patient’s environment and habits.
“Taking a full history is key to discovering triggers,” says Dr. Graffino. “It’s the little details — whether they have pets, if their house had water damage, if they are outside a lot — that help us find all the potential exposures.”
Once a full history is taken, testing may be necessary to identify exactly what you’re allergic to.
- Skin tests are the most common technique. They involve exposing a tiny extract of different allergens to the skin to gauge reaction.
- Scratch tests are used for food and airborne allergies and produce an immediate reaction (mini hive).
- Patch tests are used for topical allergies and produce a slower reaction. Here, an allergen patch is left on for 2 days and the skin is observed for 1 week to look for a reaction (rash).
- Blood tests are used for food allergies and measure antibodies in the blood. This test is helpful to determine how much of an allergen, if any, is safe to consume and in what form. For example, for some people, it’s safe to eat eggs when used in a baked product like a muffin or a cupcake, but not scrambled eggs.
Available allergy treatments
The best way to prevent allergies is to avoid triggers. Since that can be difficult, especially if you have an airborne allergy such as pollen, limit your exposure as much as possible. Change your clothes and shower after coming in from outside if it’s pollen season. Use an air purifier and lower the humidity if you’re allergic to mold spores. Ask for alternative medications if you’re allergic to the one prescribed.
Next, consider medication. Talk to your doctor about the best course of treatment. Some over-the-counter medications such as nasal steroids and eye drops may be sufficient for seasonal allergies. For more severe allergies like chronic hives and food allergies that cause anaphylaxis, biologics (medications that work on the mechanisms that lead to an allergic or asthmatic response) may be best.
“We’ve come a long way in terms of treatment options. The new biologics are delivered by injection once a month and have been shown to decrease the risk of anaphylaxis by 60-70%,” according to Dr. Graffino.
Bottom line
If you think you are allergic to something, get tested. There are many safe, effective treatment options available. You don’t have to suffer.
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