With cooler temperatures come runny noses, watery eyes and sniffling. But not all of it is due to colds and viruses.

With cooler temperatures come runny noses, watery eyes and sniffling. But not all of it is due to colds and viruses.

“We may think of autumn as prime time for colds and flu, but it’s also allergy season for many Oklahomans,” said Oklahoma Medical Research Foundation President Stephen Prescott, M.D.

Ragweed is especially plentiful in this region of the country, and its pollen can trigger allergic reactions until the first freeze. This month, Asthma and Allergy Foundation of America ranked Oklahoma City and Tulsa 5th and 10th, respectively, on its list of the worst cities for fall allergies.

But while you might blame ragweed or pollen for your stuffy nose and sneezing, Prescott said there’s another culprit as well—the immune system.

“Allergies occur when the immune system overreacts to substances that most people’s bodies perceive as harmless,” he said.

The immune system is primed to fight off invaders that can make you sick. But sometimes it gets confused. And for those with allergies, the confusion begins when the body senses a substance like pollen or dust and thinks it’s found a dangerous intruder.

“It’s the difference between coming home and finding a stranger with a gun in your house or finding a stray cat inside,” said OMRF immunologist Hal Scofield, M.D. “Neither are welcome guests, but we react to the situation differently.”

So when an allergen enters the body, the immune system attacks with antibodies. When the antibodies bind with the allergens, it releases histamine into the system. Histamines then interact with the nasal mucous membrane, causing watering eyes, congestion and runny nose.

Even though the allergens won’t harm us, our body attacks them like they would any other invader, causing an allergic reaction.

“Like most chemicals in the body, histamines do several things—one of which is keep us awake,” Scofield said. “That’s why you have to be careful with antihistamines, which cause drowsiness.”

For those with fall allergies, Scofield recommends limiting exposure to the outdoors. And before prolonged outdoor events, he suggests using nasal washes and pre-medicating with anti-allergy medications.

“With this year’s drought, allergies are likely to be worse than usual, as plants will spread more pollen to improve their chances of reproduction,” he said. “So fall allergy sufferers will want to be extra vigilant.”