Police say they were called to the Berea Walmart twice last Thursday after workers claimed to have found drugs in the store.
The first time, officers say employees told them they found a container full of filled balloons inside a dressing room just after a woman left the stall.
Investigators found that the substance inside the balloons was heroin.
Police were later called again because workers told them the woman who left the dressing room had come back to the store, but officers say when she saw them, she ran out of the store and left in a car.
They found the vehicle, stopped it, and arrested the driver.
They say 30-year-old Kelley Dillard admitted the drugs were hers, and she was charged with drug trafficking and possession.