It’s not just you; climate change is making spring allergies longer and more intense for millions of Americans. Dr Neelima Tummala from NYU Langone Health says her patients report worsening symptoms every year—and they’re not wrong.

About a quarter of US adults and one in five children suffer from seasonal allergies, bringing on sniffles, itchy eyes, and asthma attacks with varying severity. With rising temperatures and carbon dioxide levels, allergy seasons are becoming longer and more severe across the country. Heatwaves, air pollution, and natural disasters can further exacerbate symptoms.

According to the USA National Phenology Network, spring bloom arrived early in much of the US this year. AccuWeather meteorologists predict high tree pollen levels in the Ohio River Valley and parts of the Pacific Northwest, with early grass pollen spikes in the Northern Plains and Great Lakes due to warm weather and heavy rainfall. The Rockies will see intense weed pollen, while New England and some Gulf South regions might experience lower than usual tree pollen because of a cooler spring.

So as you reach for your allergy medicine this year, remember that climate change is part of the reason why allergies are getting worse—and it’s not just a seasonal irritant, but a growing health concern.