(Adds details of divested products)

WASHINGTON, April 14 (Reuters) - Generic drugmaker Akorn Enterprises Inc has won U.S. antitrust approval to buy rival Hi-Tech Pharmacal Inc on condition that it sell three generic prescription eye medications and two generic topical anesthetics, the Federal Trade Commission said on Monday.

The deal, which is valued at $640 million, will allow Akorn to expand its eye drug portfolio to oral liquids and ointments.

The divested assets will be sold to Watson Laboratories, a subsidiary of Watson Pharmaceuticals, which changed its name to Actavis PLC last year.

The divested products are generic Ciloxan eye drops, used to treat bacterial eye infections and corneal ulcers; generic Quixin drops, and a generic ointment used to treat bacterial eye infections. Akorn also agreed to divest two prescription topical anesthetics, Xylocaine and EMLA.

(Reporting by Diane Bartz; Editing by Sandra Maler and Jim Loney)