A new study states that abuse of painkiller drugs be the earliest signs that a person could abuse illegal drugs such as heroin or cocaine.

The researchers wrote in the report, which has been published in the International Journal of Drug Policy, that the change from abusing painkillers to heroin took an average of two years.
Lead researcher Dr Stephen Lankenau said that the major source of painkiller drugs came from the families. “Participants were commonly raised in household where misuse of prescription drugs, illegal drugs, or alcohol, was normalized. Access to prescription medications - either from a participant's own source, a family member, or a friend - was a key feature of initiation into prescription drug misuse”, he said.
Source-Medindia