All About Allergies

Updated August 9, 2023.

Have you ever wondered why some people have allergic reactions to harmless things like pollen while others don’t?

Allergens are tiny airborne particles such as dust or pollen that provoke an allergic reaction in some people. Most people are able to breathe in these substances without any problem. For some of us, however, these allergens provoke a well-intended but misguided immune response producing some or all of the symptoms we associate with allergy - hay fever, asthma, eczema among them.

Seasonal allergies are usually caused by outdoor allergens such as pollens from trees, grasses or weeds. Each of these plants has peak pollen periods during different months of the year in different geographical areas, so your allergy symptoms may improve or worsen during a certain season, depending where you are. But allergies can strike at any time of the year, and are a perennial problem for some people. Common indoor allergens include mold spores, animal dander, and waste from insects such as dust mites and cockroaches.

Reactions to allergens vary from person to person. The severity of the allergic symptoms waxes and wanes over a lifetime, but generally improves as you get older. If you have asthma or eczema, or have a family history of those conditions, you have a much higher risk of developing allergies.

The medical term “allergic rhinitis,” also known as hay fever, encompasses a constellation of nasal symptoms, including congestion, itching, sneezing, and runny nose. Although “rhinitis” literally means inflammation of the nasal passages, some clinicians also use the term to refer to a broader set of allergy symptoms that may include watery eyes and/or postnasal drip (drainage of nasal discharge down the throat).

The best preventive practice is to identify your triggers and reduce your exposure to them in the first place. Another drug-free approach is nasal irrigation, which flushes irritants from your nasal passages with a saline solution. Over-the-counter saline nasal sprays may provide some symptom relief, but due to the small amount of liquid used, they’re not as effective as nasal irrigation. Antihistamine medications that contain loratadine, cetirizine, or diphenhydramine may also be helpful in addressing allergic rhinitis symptoms.

Combined treatment with a nasal steroid spray often provides even better symptom control. If your symptoms don’t improve with over-the-counter medications, talk to your health care provider to determine whether this might be an option for you.

Most people with allergic rhinitis don’t need testing. Allergy testing is generally only helpful for people with severe symptoms who don’t respond to standard treatment, and whose triggers haven’t yet been identified. Allergy testing can sometimes result in false positives, which can create added confusion regarding your best course of action, and which may result in additional—sometimes unnecessary—testing.

The best way to find out what you’re allergic to is to keep a journal of triggers and symptoms, and to note where they occur – at home, work, or on vacation, for example. Be sure to note the length of your exposure and what time your symptoms began.

Most people experience very good relief of symptoms with over-the-counter antihistamines and prescription nasal steroid sprays. If you have very severe allergies, your health care provider may refer you to an allergist to determine whether allergy shots (also known as immunotherapy) would be beneficial. However, keep in mind that allergy shots are a big commitment. In the beginning, weekly in-office treatments are required, and you’ll have to stay for about half an hour afterward in case you have an adverse reaction. Over time, treatments taper to monthly intervals, but you’ll still need to get regular shots over a period of three to five years. Allergy shots also tend to be very expensive, so for most people, immunotherapy is really a last resort.