BOSTON (AP) — Massachusetts residents can rid their homes of expired or unused prescription drugs by dropping them off at sites statewide.

Next Saturday's U.S. Drug Enforcement Administration event will be the fourth National Prescription Drug Take-Back Day in the past two years.

The program has disposed of nearly 500 tons of medication at more than 5,300 sites operated by over 4,000 state and local law enforcement agencies.

More Americans abuse prescription drugs than the number of those using cocaine, hallucinogens and heroin combined, according to the 2010 National Survey on Drug Use and Health.

Massachusetts residents can find a nearby collection site by clicking here or here.

The DEA established the program to prevent old medicine from falling into unauthorized hands and to keep it from being thrown away and polluting water supplies.

Copyright 2012 The Associated Press.