"An impressive body of evidence suggests powerful effects from needle exchange programs. The number of studies showing beneficial effects on behaviors such as needle sharing greatly outnumber those showing no effects. There is no longer doubt that these programs work, yet there is a striking disjunction between what science dictates and what policy delivers. Data are available to address three central concerns:
"Does needle exchange promote drug use? A preponderance of evidence shows either no change or decreased drug use. The scattered cases showing increased drug use should be investigated to discover the conditions under which negative effects might occur, but these can in no way detract from the importance of needle exchange programs. Additionally, individuals in areas with needle exchange programs have increased likelihood of entering drug treatment programs.
"Do programs encourage non-drug users, particularly youth, to use drugs? On the basis of such measures as hospitalizations for drug overdoses, there is no evidence that community norms change in favor of drug use or that more people begin using drugs. In Amsterdam and New Haven, for example, no increases in new drug users were reported after introduction of a needle exchange program.
"Do programs increase the number of discarded needles in the community? In the majority of studies, there was no increase in used needles discarded in public places."
National Institutes of Health Consensus Panel, Interventions to Prevent HIV Risk Behaviors (Kensington, MD: NIH Consensus Program Information Center, February 1997), p. 6.