If your medicine cabinet is full of expired or unwanted medications, law enforcement officials across Iowa encourage you to safely dispose of them Saturday during National Prescription Drug Take-Back Day. The bi-annual effort is held each April and October and has led to the collection of 7,000 tons of unwanted prescription and nonprescription medication since it was established by the Drug Enforcement Administration in 2010, according to a news release. This year there are at least a dozen sites in central Iowa where medications can be dropped Saturday. Most will be open between 10 a.m. and 2 p.m., although some, including the Urbandale Police Department, will open at 8 a.m.