ST. PETERSBURG, Fla. (AP) — Pollen: It’s on your car, in the air and especially in your sinuses.

From Florida to Texas to Colorado, 2010 is shaping up to be a monster of an allergy season. The words “pollen” and “allergy” are among the top 10 trending topics on Twitter in several U.S. cities. Everywhere, it seems, is covered in a fine yellow dust that irritates our lives. Experts say it’s the worst they’ve seen in years.

“It’s wicked bad this year,” said Dr. Mona Mangat, an allergy specialist in St. Petersburg, Fla., who can’t recall a worse year in the six she’s worked there. “We’re just overwhelmed with patients right now. We’re double- and triple-booked with new patients, trying to work people in because we know how much people are suffering.”

And they are suffering a lot. Take 5-year-old Sam Wilson of St. Petersburg. His mom gives him Claritin in the morning, Nasonex and Benadryl at night, and he receives four allergy shots every week. The sidewalks of his hometown are covered in what look like piles of dried, brown worms — but they are mounds of oak tree pollen.

The boy’s mother said that when the pollen is at its worst, his eyes water and itch, he can’t breathe through his nose and his throat burns.

“His reaction yesterday was pretty bad,” said his mother, 34-year-old Joanna Wilson on Thursday. “He couldn’t breathe, he was completely congested, and crying.”

Oak trees are the culprit in many places in the Southeast.