For millions of people, April brings aggravating allergies.

An immune response to one's environment, allergies cause the body to become hypersensitive to certain substances, such as pollen.

Saturday, a local Rite Aid store will offer free clinical allergy screenings to help allergy sufferers identify the cause of their symptoms.

The screenings, known as fluorescent allergosorbent tests, will test for the most common allergens, including ragweed, grass, mold, wheat, egg, milk and cats.

A nurse will take a blood sample and send it to a laboratory for testing, Rite Aid spokesman Eric Harkreader said. Patients will get their results within three weeks, he said.

"Health screenings are especially important for Rite Aid customers who lack access to preventive care or who may not have the time to schedule an appointment with their physician," he said.

To receive a free screening, visit the store, 3300 E. Market St. in Springettsbury Township, between noon and 4 p.m. Saturday. There are a finite number of screenings available.

"We do recommend customers get there early," Harkreader said.

- Reach Mollie Durkin at mdurkin@yorkdispatch.com.