The recent rainy weather around Iowa’s not far from our average climate this time of year. Iowa allergy specialist Dr. John Wyler says the good news is, the tree-pollen season’s winding down the end of May.He says grass-pollen season continues from May to the end of June, and rain determines the amount of pollen, though dry times let it spread by air. Dr. Wyler explains those “aero-allergens” are the ones you’ll suffer if you are one of the many sensitive people bothered by pollen.Many medications are available like sprays and antihistamines, but you can also get allergy shots, a kind of immunotherapy. Dr. Wyler admits the scheduled shots fell out of favor for a time among some doctors and patients. He says there’s a resurgence of interest as we get better samples of allergens and refine the medications that treat their symptom-causing components. Wyler says there are a host of very promising drugs just over the horizon. In the next five years he expects to see many new medications being tested and approved for use. Wyler was an allergist at University of Iowa hospitals for years, and now is affiliated with a center in Iowa City that does clinical tests of allergy treatments.