One of the oft-discussed mysteries of heroin: In spite of widespread use by US soldiers during the war in Vietnam, most did not continue use after returning Stateside. But others did, and some are still addicts today. Heroin is certainly an addictive substance, so why didn’t all the veterans continue using it?

That left scientists in search of an explanation. They looked for factors that might contribute to different outcomes. That included both risk factors and protective factors.

A 2003 study involved analysis of structured interviews with 374 returning veterans who acknowledged having used heroin in ‘Nam. The interviews themselves had taken place back in  1973, right around the time US involvement in Vietnam came to an end. The analysis came some thirty years later.

Drug use in the stress of a combat zone is never a surprise to experts. That was particularly true for Vietnam, given Southeast Asia’s reputation as a center of the world heroin trade. It would have been more surprising had drug use not increased.


One important consideration: Most of the study subjects said they had not injected heroin. They’d snorted or smoked it.  That’s of interest because injection is often a sign of escalating dependence. The usual pattern among addicts is to progress to intravenous use as increased tolerance and withdrawal render other forms of ingestion inadequate.

Soldiers who injected heroin while overseas were more likely to inject it after their return to the US.

Other Factors

It was also an era of widespread conscription– the draft. That translates to less selectivity in new recruits. Recruits arrived with histories of recent drug use or conduct problems that would no doubt have eliminated them from today’s volunteer military. Antisocial personality traits in particular are associated with increased risk for all types of substance abuse.

Looked at this way, the study findings seem to suggest that soldiers who were already at risk for substance problems– meaning those who were using drugs or experiencing certain behavior problems– found Vietnam to be fertile ground for escalating drug use and dependence. That dependence was likely to continue when they returned home. While others, without that vulnerability, were more likely to leave heroin behind.

Those who are interested can check out the study here.

Please Comment Below