Here we go again.

Another season of sneezing, itchy eyes, runny noses. The trees may not be leafing out just yet, but pollen fills our air all the same.

Here to help us sort it all out – what to do, what’s new – is Scott Feldman, assistant professor of medicine at the University of Pennsylvania’s Perelman School of Medicine. As a member of Penn’s allergy and immunology treatment team, he specializes in allergic disease management.

How is this year shaping up? Did the late cold weather change anything?

While I’m not a botanist, it’s well-understood that when the weather turns warm, plants get signals to start their pollination. Trees are springtime. Grasses are summer. Ragweed is fall. The later onset of warm weather, as we had this spring, is going to delay when the trees start pollinating. But that does not necessarily mean there will be less pollen.

With certain winds, pollen can travel dozens, if not hundreds, of miles. So in the greater Philadelphia area, while you may not see one single tree pollinating outside your home, that does not mean pollen will not be affecting you. I usually counsel my patients who are allergic to tree pollen to start their preventive allergy medications sometime around Valentine’s Day, so they’re ready.

By mid-April, we may be having some very high tree pollen counts.

Many people who do not have allergies develop them as they age. If I start sneezing this spring, how do I know whether it’s an allergy or a cold?

People who notice predictable symptoms at the same time every year could be evaluated for allergies. But if you’re sneezing and having problems in late February, and you check the pollen counts and they’re low, plus you just came back from an airplane trip or were around sick people, it’s likely a cold. We run into this in the fall. The ragweed season coincides with the virus season and children going back to school. Also, viruses last only a week or so. So, if you’re having symptoms that persist every year, it’s more likely to be allergies.

Scott Feldman, M.D.
University of Pennsylvania
Scott Feldman, M.D.

There are irritants that will affect all people at a certain threshold. If you’re inside a burning building, and there’s a lot of smoke, you’re going to cough, and your eyes will water, and your nose will run. However, the amount it takes to set that off might vary from person to person. Allergens in general are all under the umbrella of hypersensitivity reactions. Your immune system has a more robust reaction than otherwise because you have what’s called an allergic antibody that is specific to some substance -- from tree pollen, to pets, to peanuts. When your immune system interprets that substance as something foreign, you have a predictable reaction.

In terms of developing allergies later in life, this is possible through what’s called sensitization. That process often takes about three years, or maybe three seasons. For example, someone who moves to the Philadelphia area from the West Coast, after three years of experiencing springs and falls with different kinds of pollen, may start to develop allergic symptoms. Experts think that the higher amounts you breathe in, the more likely you are to develop an allergy to that substance.

I should note that adult-onset food allergy, on the other hand, is very rare. That’s because the immune system in your gut is very different from the immune system in your lungs. It is very unusual to have tolerated a food for many years and then develop a new allergy to it.

Is climate change already affecting allergy season?

Surveys and data can be found on the American Academy of Allergy, Asthma and Immunology website. There does seem to be some relationship between the amount of carbon dioxide in the atmosphere and how that affects the pollination of plants and grasses. So it makes sense that weather patterns have increased the amount of pollen in the air. Plants may have stronger signals to make more pollen, or there may be more plants.

If there is more pollen every year, then allergies may get worse every year. In general, your allergic symptoms are directly proportional to the amount of allergen you’re exposed to. For example, if you’re allergic to cats and you go to someone’s home that has eight cats, the amount of allergen you’re going to breathe is more than if you go to someone’s home that has one cat in the living room and you’re in a different room. So, unsurprisingly, the more pollen in the air, the worse your symptoms are likely to be.

Are there any promising new treatments for allergies?

Not as much for environmental allergies. A lot of the hot research is in areas like food allergies, as they are potentially more severe and life-threatening. There are various clinical trials looking at things like oral immunotherapies or the so-called peanut patch -- a way of giving you slowly increasing amounts of food to make you less allergic.

In terms of environmental allergies, the two big interventions -- nose sprays and antihistamines -- generally work pretty well, as long as everything is used correctly and regularly. Allergy shots have been around a while and are fairly effective.

One new area is sub-lingual immunotherapy, or SLIT. Sub-lingual means under the tongue. Rather than getting an allergy shot every week or every month, you put the substance under your tongue every day to desensitize your immune system so it will react less strongly to the allergen. It is specific to individual allergens. There are a couple products for grass and one for ragweed on the market now. Researchers are still working on tree pollens and other allergens. But it’s not really clear yet how well they work. The usual catch phrase applies: Discuss with your doctor whether this treatment is right for you.

Meanwhile, what are some tried and true tactics people can use to lessen their allergic symptoms?

The first thing is to use the correct nose spray technique. Otherwise, you won’t experience the full effect. You want the spray to go into your sinuses and stay in your sinuses. The bottle should be placed comfortably in the nostril, generally pointed toward your ears. What you don’t want to do is spray your septum, in the middle of your nose, because that’s not where the allergic reaction is happening. The other thing is, many people are overachievers and feel the need to snort their medication strongly. That causes a lot of the medication to go down into the back of the throat. If you’re tasting the medication, that means it is ending up in your throat and not in your nose. Sniffing gently is a significant improvement.

The other thing is that with a lot of pollens, the counts tend to peak in the morning. One of the things we counsel is avoidance measures. For example, if you’re allergic to grass, cutting your grass early in the morning when the pollen count is high is not the best thing to do. A bedroom window open overnight may also enable outside pollen to enter while you’re sleeping. Little changes in your habits can minimize the amount of exposure you have.