Sales of oxycodone and hydrocodone are sharply rising in areas of the United States where these prescription painkillers were not as popular in the past, according to an analysis by the Associated Press. The rise in sales is driven by an aging population with pain issues, as well as an increase in addiction, experts say.

The AP found a dramatic increase in the distribution of oxycodone between 2000 and 2010 in areas including New York’s Staten Island and Santa Fe, New Mexico. Hydrocodone use is rising in Appalachia and in the Midwest, the AP found, after analyzing data from the Drug Enforcement Administration. Painkiller sales are spreading rapidly in areas where there are few resources to treat people who become addicted.

The increase in prescription painkiller use coincides with a rise in overdose deaths and pharmacy robberies, the article notes.

The number of Americans who died from overdoses of prescription painkillers more than tripled in the past decade, according to the Centers for Disease Control and Prevention (CDC). More people now die from painkillers than from heroin and cocaine combined. An estimated 14,800 people died in the United States from painkiller overdoses in 2008, a more than threefold jump from the 4,000 deaths recorded in 1999, the CDC said in a report released last November.

While 40 states have prescription drug monitoring programs, many are not linked together, according to the AP. That means patients can go from one state to another shopping for pills. Currently there is no federal monitoring of prescription drugs at the patient level.