Prescription drug abuse increased 75 percent from 2002-10, according to a new study from the Centers for Disease Control and Prevention.

In just five years, the number of emergency room visits prompted by the misuse of prescription drugs nearly doubled, the CDC reported. More than 15,500 people die from overdose annually.

The problem is particularly pronounced among those age 50 and older, according to the National Institute of Health. The rapid rise prompted the organization to issue its first consumer alert for seniors last month.

Addiction may be spurred in part by lack of knowledge about the dangers of prescription drugs, Counsel&Heal reported. Among older adults, 50 percent fail to notice prescription drug warning labels, according to a recent study from Kansas State University. Researchers are calling for updated packaging.

For the spike in deaths, some blame physicians for relying on drugs that are unsafe, according to Time Magazine. A second report from the CDC shows methadone accounts for nearly one in three prescription painkiller overdose deaths.

Doctors started prescribing methadone, which is best known for its use in addiction treatment, as a pain killer in the late 1990s after drug addicts figured out a way to get around Oxycontin's time-release mechanism by crushing and snorting. methadone is long lasting like Oxycontin, but is 12 times cheaper.

The drug is long-lasting and builds up in the body. It is considered safe for addicts, who have already worked up a tolerance for the opioid. But when given to a patient who has no history of opioid abuse, it can slow breathing and disrupt heart rhythm.

"This means that taking methadone three times a day — exactly as prescribed — can lead to a potentially fatal overdose if the person is not fully tolerant to the drug," wrote Time reporter Maia Szalavitz. "Worse, the effects vary widely from person to person."

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