Millions of bottles of eye drops have been recalled nationwide due to the potential presence of a foreign substance.

Manufacturer Lupin Pharmaceuticals recalled 2,530,182 bottles of Prednisolone Acetate Ophthalmic Suspension eye drops, according to a Food and Drug Administration enforcement report filed last month.

Big picture view: The recall was initiated on June 4 but was recently classified as a Class II recall on June 30.