Clean needle exchange programs may be both helpful and harmful

Here's a recent NBER working paper that looks at the effects of opening a place where intravenous drug users can get clean needles--it finds that this reduces blood borne disease, but may in fact increase drug use.

Are Syringe Exchange Programs Helpful or Harmful? New Evidence in the Wake of the Opioid Epidemic
by Analisa Packham
NBER Working Paper No. 26111,  July 2019

Abstract: "In light of the recent opioid crisis, many public health entities have called for an expansion in syringe exchange programs (SEPs), which provide access to sterile syringes and facilitate safe needle disposal for injection drug users. This paper investigates the effects of recent SEP openings on HIV diagnoses and drug-related overdoses in the wake of the opioid crisis. I find that SEP openings decrease HIV diagnoses by up to 18.2 percent. However, I present new evidence that SEPs increase rates of opioid-related mortality and hospitalizations, suggesting that needle exchanges alone may be less effective than other interventions at stimulating recovery."


"From an economic standpoint,SEPs have the potential to create large positive externalities by reducing the stock of used needles on the streets and preventing the spread of disease. Conversely, by providing clean needles to drug users, reducing the stigma of using drugs and/or creating a safe environment for networking with other users, SEPs may also generate untended consequences. In particular, lowering the cost of obtaining needles and other supplies incentivizes drug users to inject more frequently, potentially exacerbating rates of opioid misuse and abuse. 

"In this paper, I test the causal relationships between SEP openings and drug-related health and crime outcomes. Because no official national directory of SEPs exist, I construct a hand collected dataset on program locations and opening dates to identify areas exposed to SEPs within the last ten years. In particular, using health outcomes data from the CDC, I compare rates of HIV, drug- and opioid-related deaths, opioid-related overdoses, and drug-related crime in counties with SEP openings to other counties without SEPs before and after the initial year of implementation. I find that SEPs decrease the number of HIV cases in some areas, and that  this effect grows over time. However, estimates also indicate that SEP openings increase drug-related mortality. … Effects are largest in rural and high-poverty areas, suggesting that those with larger geographic or financial obstacles  to substance abuse treatment are most affected by such programs."