Each year, as many as 80 million Americans experience seasonal allergy symptoms: nasal congestion, runny nose, sore throat, sneezing, and itchy eyes. Over-the-counter medication may provide some relief, but they also might be the sneaky culprit behind dry, sensitive, and watery eyes.
Dry eye syndrome manifests in many ways. For some, eyes may feel more tired or sensitive. Others may experience burning, more tear production than usual, or blurry vision. The symptoms occur when the eye doesn’t produce enough healthy tears to keep the eye’s surface moistened. This may be due to hormones, environmental factors, using contact lenses, stress, and even some medications.
“Sometimes the treatments that help make the nose less runny can make the eyes more irritated by drying them out a bit more,” says Darren Gregory, MD, professor of ophthalmology at the University of Colorado School of Medicine.
Gregory, who specializes in dry eye, says when new patients come into the clinic with dry eye symptoms, he reviews the medications they’re using. Antihistamine medications can be a contributor to what’s causing their uncomfortable symptoms.
Antihistamines, which are commonly found in allergy medications, block histamines, chemicals produced by the immune system when a person encounters an allergy trigger, like pollen or dust.
Histamines cause the symptoms most often associated with seasonal allergies and the common cold. They can cause swelling in nasal tissue, which can lead to a stuffy nose, and other symptoms, including a runny nose and watery eyes.
“The conjunctiva, which is the skin that lines the white part of the eye and the backs of the eyelids, is very similar to the skin that lines the inside of our nose,” Gregory says. “So, the same things that irritate the nose can also irritate the eye.”
Antihistamine medications can alleviate these seasonal allergy symptoms, but Gregory explains that oral antihistamines all have some degree of anticholinergic side effects that can dry the eyes and the mouth in the process of drying out nasal passages.
“For patients that already have significant dryness of the eyes, sometimes during allergy season using something other than an oral antihistamine, like a nasal corticosteroid spray, can be more helpful,” Gregory says. “They can decrease the allergy misery without having that dryness effect on the eyes.”
“You have to balance out the pros and cons of every treatment,” he adds.
Health researchers estimate that as many as 344 million people around the globe experience dry eye. Symptoms include burning, stinging, redness, a foreign body sensation, or feeling a general grittiness in the eyes.
Additionally, excessive tearing can occur. Dry eyes are more easily irritated, which can cause occasional gushes of tears that are produced in response to irritation and lead to tearing, even though the underlying problem is dryness of the eyes.
Allergy season can make it particularly difficult to know what’s causing the tearing. It may be an allergen irritating the eyes or it may be the medication used to prevent the reaction to the allergen, or a little of both.
“It's common for people who have dry eyes to have occasional watering of the eyes, and that can be worsened by allergies,” Gregory says. “It gets a little tricky sometimes to sort out and decide what treatment is most likely to be helpful. Treatments for dry eye range from over-the-counter artificial tears, which can be purchased at most grocery stores, to prescription medication.
Whether it’s allergy season or not, Gregory recommends taking steps to mitigate environmental factors that can lead to dry eye. Avoiding windy environments, indoors and out, taking time away from screens during the day, and using moisturizing drops may all help mild symptoms.
If dry eye symptoms persist, Gregory recommends talking with an ophthalmologist who can help pinpoint the root causes of the symptoms and recommend targeted treatments.
“Dry eye can be really uncomfortable for patients and potentially damaging to the ocular surface, so it’s best to see a specialist if it’s starting to bother you,” Gregory says. “It’s important to remember that treating dry eye, especially in dry climates or when seasonal allergies are peaking, may take some trial and error, but there are treatments that can help.”