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Delaware’s allergy season typically starts in March and can last through October. Here’s what triggers allergies and how to remedy symptoms.
April showers may bring May flowers, but for people who suffer from seasonal allergies, those showers can also result in months of sniffling, sneezing, watery eyes and wheezing.
Allergies are the sixth-leading cause of chronic illness, and more than 50 million Americans, including children and adults, suffer from allergies each year, according to the Centers for Disease Control and Prevention.
What Causes Allergies?
Allergies occur when your immune system reacts to an allergen—a normally harmless substance such as pollen, grass, mold, dust, pet dander or food—and tries to fight it off like a germ or virus. This causes symptoms such as itching, sneezing, hives, shortness of breath, and in the worst cases anaphylaxis, a severe, life-threatening reaction that results in the inability to breathe.
The most common allergens in the Brandywine and Delaware valleys are pollen, trees, grass, weeds and mold. Dust mites, pet dander, certain foods and bee stings are also problematic for many.
Allergists typically recommend avoiding contact with your allergic triggers as much as possible. They may prescribe a variety of over-the-counter (OTC) or prescription medications, as well as immunotherapy treatment—allergy shots—if necessary.
“When you begin to see cars coated in green dust around the neighborhood, you know it’s allergy season,” says Gregory Marcotte, M.D., of ENT & Allergy of Delaware in Wilmington, who also serves as section chief for allergy for ChristianaCare.
“While people sometimes develop environmental or food allergies for no apparent reason, genetics and family history are the most common cause of allergies.” If both of your parents have allergies, he explains, you’re likely to inherit them as well, except when it comes to food.
“Climate change, which has caused a warmer climate and longer growing seasons, has also resulted in an increase in hay fever and asthma, a more severe degree of allergies,” Marcotte says.
Unfortunately, we live in an environment that’s ripe for allergies from March through at least October.

“Spring allergies typically start in the beginning of March, when the trees begin to bloom and release their pollen,” says Michael Wydila, M.D., of Allergy Associates PA, which has offices in Wilmington and Newark. “Contrary to popular belief, ornamental, flowering trees like cherry blossoms don’t bother people pollenwise. The most pollen-producing trees include maples, oaks and elms.
“In mid-to late April through mid-July, we start dealing with grass pollen, and by June most of the tree pollen is gone,” Wydila continues. “From summer to mid-August, ragweed starts blooming. In early fall, weeds start emerging that could affect allergy sufferers, and in October, molds emerge following the rainy season.”
In addition to environmental allergies, many people suffer from perennial, or recurring, allergies to dust mites and pet dander.
“Dust mites live in bedding and feed off of dead skin flakes,” Wydila explains. “Allergies get triggered by breathing in their feces.” The best way to combat dust mites is to dress bedding (including mattresses and pillows) in specially designed allergen-proof, impermeable covers, wash bedding weekly in hot water, keep the humidity in your home below 50 percent and vacuum regularly.
A pet allergy is also frequently triggered by exposure to the dead flakes of skin, or dander, that an animal sheds. You can also have an allergic reaction to proteins found in an animal’s saliva or urine. Signs of a pet allergy include sneezing, a runny nose and watery eyes; an itchy nose, roof of mouth or throat; and symptoms of asthma, such as wheezing and difficulty breathing. Doctors recommend keeping pets out of the bedroom and away from furniture, as well as using a HEPA filtration system in the home and, again, vacuuming frequently.
Take a Bite out of Food Allergies
“Unlike environmental and perennial allergies, food allergies are more likely to affect children and are typically not inherited,” Marcotte says. “Unfortunately, food allergies are becoming more of an issue, affecting about 10 percent of children.” The most common triggers include peanuts and tree nuts, eggs, milk, wheat, soy, fish and shellfish.
Doctors don’t really know why food allergies are increasing in children, but Marcotte notes there are a few hypotheses for the growing incidence, which include:
- Improved hygiene: Children are not getting as many infections, which results in fewer exposures to allergens. If the immune system is not challenged at a young age, it can start reacting in a negative way against harmless things.
- Exposure theory: Doctors previously told parents that avoiding certain foods like peanuts before age 2 would help prevent developing an allergy. Numerous studies have reported that the opposite is true: Kids tend to develop a tolerance when exposed to these foods/allergens earlier in life. Some even assert that by consuming these foods while pregnant, a mother can reduce her child’s risk of food allergy.
- Your biome: Imbalances in the beneficial bacteria inside your gut, or microbiome, may result in a greater likelihood of developing an allergy.

While there is no specific treatment for food allergies (other than avoidance and the need to carry an adrenaline or EpiPen in case of an emergency), oral immunotherapy is beginning to show progress toward desensitizing patients to the foods they’re allergic to.
Oral immunotherapy involves administering low doses of a particular allergen—such as a daily dose of peanut flour for 2 1/2 years—to build up an individual’s tolerance to that allergen. The goal is to gradually increase the dose to desensitize the patient to the allergen and minimize the chance of an allergic reaction.
“The best method for addressing a food allergy remains teaching children to know what foods they’re allergic to and avoid any contact with that particular food, in addition to carrying an EpiPen with them at all times,” Wydila says.
To determine what, exactly, a patient is allergic to, allergists typically perform a skin test during which small amounts of purified allergen extracts are pricked onto the skin’s surface. For 15 minutes, the practitioner observes the skin for signs of allergic reactions. If you’re allergic to a particular substance, you’ll develop an itchy red bump where that allergen was applied. A blood test that screens for specific allergy-causing antibodies to common allergens is another diagnostic option.
An Ounce of Prevention
The first line of defense when it comes to treating allergies is avoidance.
In addition to keeping your space clean, “the best way to minimize symptoms or reduce exposure to allergens is to keep your windows closed in the spring when pollen counts are higher and run your air conditioning in the summer,” Marcotte says.
If you’re still experiencing symptoms from seasonal allergies, your doctor may prescribe a variety of oral antihistamines or nasal inhalers. OTC medications include allergy tablets and nasal sprays.
“Too many people wait until their symptoms are bad before they start taking allergy medications, which is counterproductive,” Wydila says. “If you know you have seasonal allergies, it’s important to be proactive and start taking your medications a week or two before allergy season begins to give your body time to build up the medications in your system.”
If OTC medications don’t alleviate your symptoms, allergy shots—also referred to as immunotherapy—can provide individualized, long-term treatment for allergy sufferers.
“Allergy shots are the closest thing to a cure we can offer our patients,” Marcotte explains. “People typically receive allergy shots for three to five years to essentially ‘turn off’ their allergies. The shots are not medication, so they’re more holistic, and they help people build up a tolerance to their allergens.”
Each allergy shot contains a small amount of the specific allergen that triggers a person’s allergic reactions. The shots contain just enough of the allergen to stimulate the immune system without causing a reaction. This boosts tolerance to that allergen. Some people can successfully stop their allergy shots after a few years. Others may have a recurrence later in life and need to resume the treatment.
“For people who don’t tolerate shots well or prefer not to [frequent] a doctor’s office, allergy drops or tablets, which are placed under the tongue and dissolved in the mouth, provide another treatment option,” Marcotte notes.
No matter what you’re allergic to, allergies don’t have to hold you back from living your best life, whether it’s getting outdoors in nature, eating out or spending time with a beloved pet. Your allergist can help you make lifestyle changes that work around your allergies so you can enjoy your life and protect your health.
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