Illegal use of prescription pain drugs increases a person's risk of becoming a heroin user, a US government report suggests.
The researchers found that Americans aged 12 to 49 who had used prescription pain relievers illegally were 19 times more likely to have started using heroin within the past year than other people in that age group.
Nearly 80% of people who recently started using heroin had previously used prescription pain relievers illegally, the US Substance Abuse and Mental Health Services Administration report added.
It also noted, however, that only 3.6% of people who had illegally used prescription pain medicines started using heroin within five years.
"Prescription pain relievers, when used properly for their intended purpose, can be of enormous benefit to patients, but their nonmedical use can lead to addiction, serious physical harm and even death," Dr Peter Delany, director of SAMHSA's Center for Behavioral Health Statistics and Quality, said in an agency news release.
New dimension of harm
"This report shows that it can also greatly increase an individual's risk of turning to heroin use thus adding a new dimension of potential harm," Delany said.
The number of Americans who reported that they used heroin in the past 12 months rose from 373 000 in 2007 to 620 000 in 2011. During the same period, the number of people who reported heroin addiction in the past 12 months increased from 179 000 to 369 000, and the number of people who started using heroin for the first time in the past 12 months climbed from 106 000 to 178 000.
Between 2008 and 2011, the number of people who started using heroin increased among adults aged 18 to 49, but there was no change in the rate among youths aged 12 to 17. During the same period, there was an increase in the number of people with annual incomes of less than R512875 who started using heroin, the report said.
The number of people who started using heroin in the past 12 months rose sharply in all regions of the nation except in the South, where the rate stayed the lowest in the country. Blacks were less likely than other racial and ethnic groups to start using heroin.
The U.S. National Institute on Drug Abuse has more about heroin.