AUGUSTA — The federal government says nearly 12,000 Maine residents who receive Medicare saved $6.3 million on their prescription drugs in 2011 due to changes in the health care overhaul law.

The Department of Health and Human Services also says savings for people with Medicare will increase over time to nearly $4,200 by 2021 because of the Affordable Care Act.

The law provides a 50 percent discount on brand-name prescription drugs, and this year a 14 percent discount on generics. Last year, it provided a 7 percent discount on covered generic medications for people who hit the prescription drug coverage gap known as the doughnut hole.