[waterfowl]

Because IV is the only way to do heroin. Lots of "casual drug users" are into pills/narcotics, which end up being too expensive, so they get into heroin and wreck themselves.

To be fair I only know a couple people who say they "occasionally do heroin" and I'm not sure if I believe them, but I would say a huge proportion of heroin users do not initially IV(you can smoke or snort, same with crystal, people tend to progress to IV when they feel they are no longer getting "high enough").

[vidarh]

IV isn't the only way to do heroin. It is however the most "effective" way to do heroin, both in terms of cost and high, and cost is often one of the things that drives people from prescription opiates to heroin.