Itchy eyes. Scratchy throat. Runny nose. They’re all symptoms of seasonal allergies, which will wreak havoc on people this spring. We asked Karen Horbowicz, an assistant clinical professor in the Bouvé College of Health Sciences’ School of Pharmacy, to discuss what causes seasonal allergies, whether the mild winter will affect allergy season and how people can reduce their chances of suffering.

What causes allergies? Why are some people, but not others, affected?

A person’s likelihood of developing seasonal allergies depends upon his or her immune system. There is no primary reason for developing seasonal allergies, but if your parents have them you are at a greater risk. Seasonal allergies are caused by an immune response after multiple exposures to pollen from grass, trees, flowers and weeds. This will ultimately result in the release of histamine from mast cells found in your eyes and nose. Histamine is a substance that causes irritation and inflammation, which leads to the typical symptoms of seasonal allergies, such as itchy, watery eyes, runny nose and scratchy throat.

How will the mild winter affect the severity of this year’s allergy season?

Given the mild nature of this winter and the unseasonably warm weather, we can expect to have an earlier onset of allergy season. Trees have already begun pollinating, which we can expect to continue as the weather warms up. Additionally, flowers have begun to sprout, indicating that their pollination will also begin sooner than usual. The severity of the pollen counts remains to be seen.

What are some tips for reducing the effect of allergies this spring?

One way is to reduce your exposure. Pollen can be stirred up on windy days and is usually lower after a rainstorm. Pollen counts are also typically higher earlier in the morning. Try to stay indoors when pollen counts are high, keep doors and windows shut if possible, and avoid mowing the lawn or gardening if you have seasonal allergies. To find the pollen count in your area, visit http://www.weather.com/outlook/health/allergies/weather.

Another important step is to talk to your pharmacist about what over-the-counter products would be best for you. But some general advice includes taking nonprescription antihistamines before symptoms begin. A nonprescription ophthalmic antihistamine is also available to help treat eye symptoms. These products block histamine’s effects thereby reducing symptoms.

If oral antihistamines are not enough, try an oral decongestant. Nasal decongestants are also available, but should not be used for more than three days, and prolonged use may actually worsen nasal congestion upon discontinuation. Decongestants work by narrowing blood vessels in the nose, which reduces swelling. But they should not be used in patients with high blood pressure, glaucoma or prostate conditions.

Another nonprescription drug product is cromolyn nasal spray. This product works best if used at least one week before symptoms manifest because it may take up to two weeks to see the full effect. This product works best by preventing mast cells from releasing histamine.

Finally, if you are still suffering, talk to your doctor about prescription medications to help with seasonal allergy symptoms.