RIVERSIDE, Calif. -

More than 13 tons of unused prescription drugs were collected in Riverside and six other counties during National Prescription Drug Take-Back Day on April 27, it was announced today.

Local law enforcement agencies from Riverside, Los Angeles, Orange, Ventura, Santa Barbara, San Bernardino and San Luis Obispo counties collected the potentially dangerous medications from members of the public during the sixth annual event, according to the U.S. Drug Enforcement Administration.

Many collection sites provided "drive-thru" service for convenience. Community groups and coalitions also joined with local law enforcement agencies to provide drug awareness literature and community resource information.

According to a 2011 Substance Abuse and Mental Health Services Administration survey, twice as many Americans regularly abused prescription drugs than the number of those who regularly used cocaine, hallucinogens, heroin and inhalants combined.

That same study revealed more than 70 percent of people abusing prescription pain relievers got them through friends or relatives, a statistic that includes raiding the family medicine cabinet.

A total of 371 tons of prescription drugs were collected nationwide during take-back day this year.