People who suffer from seasonal allergies know that spring can feel challenging. Flowers, trees, and grasses are in bloom and growing, meaning pollen and other allergens are in the air.
In the U.S., an estimated 18 million adults have hay fever or allergic rhinitis caused by pollens, weeds, grasses, and molds. Other people may have environmental allergies to animals and dust mites.
Can You Develop Allergies Later in Life?
You can develop allergies later in life, even if you’ve never suffered from the condition before. The term for this phenomenon is adult-onset allergies.
Here are some key points about developing allergies as an adult:
- Adult-onset allergies can occur at any age, but they most commonly appear during young adulthood, the 20s and 30s.
- Common adult-onset allergies include seasonal allergies to pollen, mold, dust mites, pet dander, and food allergies, including shellfish, peanuts, and tree nuts.
- Developing food allergies as an adult is relatively common, with studies showing around ten percent of food allergies in adults were adult-onset.
- Moving to a new geographic area with different environmental allergens sometimes triggers higher exposure levels, making an allergy seem new.
- The reasons why some people develop allergies later in life are not fully understood. Still, potential factors include genetics, changes in the immune system with age, exposure to new environments and allergens, and even hormonal shifts.
- In other cases, the allergy may have been present but unnoticed until adulthood, when the immune system’s response changes.
Is It Allergies?
Determining whether the symptoms you’re experiencing are allergies or something else isn’t always easy.
Typical allergy symptoms include:
- Coughing due to postnasal drip.
- Frequent throat clearing.
- Itchy and watery eyes.
- Nasal congestion.
- Runny or stuffy nose.
- Sneezing.
- Sore or scratchy throat.
These symptoms are also often associated with the common cold and flu. And though some symptoms overlap, there are differences.
For example, colds typically present with a runny or stuffy nose, sneezing, sore throat, and an often wet and hacking cough. Symptoms of the flu are similar but generally more severe than those of a cold.
But viruses cause both of these illnesses, which are contagious — spreading easily between people. This means multiple people in your family might develop similar symptoms at one time. Their symptoms won’t respond to antihistamines and generally get worse before they get better.
The flu often comes on suddenly and includes symptoms such as a high fever (102 F to 104 F) that lasts for three or four days and severe body aches. It can also bring on fatigue that can last up to three weeks and a dry cough that can become severe.
If you’re experiencing any of these symptoms, talk to your doctor. They can help you determine the next steps for treatment.
How Do Allergies Develop?
Allergies can develop at any point in a person’s life. Usually, allergies first appear early in life and become a lifelong issue.
However, allergies can start unexpectedly in adults. A family history puts you at a higher risk of developing allergies at some point.
Allergies develop when your body thinks a substance such as animal hair, pollen, or mold is harmful. That substance awakens your immune system to release histamine, leading to allergy symptoms.
Your immune system may weaken as you age, so your response to an allergen may also weaken. However, repeated exposures can cause your immune system to overreact.
If you develop allergies as an adult, you may have had slight symptoms throughout your life. But then an event such as a move or a new pet triggered your immune system to respond.
Why Do I Keep Getting Allergies?
Allergies can persist or recur due to continuous exposure to allergens or immune system changes.
Common reasons for recurrent allergies include:
- Repeated exposure — Continuous exposure to allergens like pollen, dust mites, or pet dander can cause persistent symptoms.
- Immune system changes — Aging or other factors that weaken the immune system can increase allergen sensitivity.
Why Am I Suddenly Allergic to My House?
Suddenly developing allergies in your home environment can make you feel distressed.
Common household allergens include:
- Dust mites — Tiny creatures that thrive in bedding, upholstery, and carpets.
- Pet dander — Skin flakes from animals can trigger allergic reactions.
- Mold — Can grow in damp areas like bathrooms and basements.
- Cleaning products — Air fresheners, carpet cleaners, and other products can trigger allergies.
Can You Be Allergic to Air?
A direct allergy to air itself isn’t possible. But various airborne particles or contaminants in the air you breathe can trigger allergies. These are airborne allergies (also known as aeroallergens).
Some people can develop a rare condition called cold urticaria. For those who do, exposure to cold air can trigger hives, swelling, and (in severe cases) anaphylaxis.
What Are Some Signs of an Allergy?
Though many symptoms can indicate an allergy, three common signs are:
- Itchy and watery eyes.
- Nasal congestion.
- Sneezing.
Are My Symptoms Allergies?
If you believe you’ve developed allergies, try over-the-counter antihistamines to help control your symptoms. It’s also a good idea to avoid what you think you are allergic to until an allergist can see you.
An allergist can test you to determine your allergies and precisely what triggers your allergy symptoms. If testing confirms allergies, you can work with your doctor to develop a tailored care plan.
How Are Allergies Treated?
The first step is to avoid what you are allergic to and try over-the-counter antihistamines.
If that doesn’t work, your doctor may recommend one or more of the following allergy treatment options:
- Allergy injections or immunotherapy — A series of injections to desensitize your immune system to the allergens that trigger your symptoms. This treatment aims to retrain the immune system to recognize the allergen as not dangerous, decreasing the frequency or severity of allergy symptoms.
- Inhalers — Medications inhaled into the lungs that open your airways. Inhalers can include daily use or rescue inhalers used for immediate symptom relief.
- Nasal sprays — Medications that reduce the swelling in your nose, which causes a stuffy, runny, and itchy nose.
- Prescription antihistamines — Most antihistamines are now over the counter, but some are only available by prescription.
Allergies can make you feel unpleasant no matter how old you are. Your doctor can help you determine what’s triggering them and develop a treatment plan that works for you.
Editor's Note: This article was originally published on , and was last reviewed on .