Harm Reduction: When Does It Improve Health, and When Does it Backfire?
A subset of harm reduction strategies encourages individuals to switch from a harmful addictive good to a less harmful addictive good; examples include e-cigarettes (substitutes for combustible cigarettes) and methadone and buprenorphine (substitutes for opioids). Such harm reduction methods have proven to be controversial. Advocates argue that people struggling with addiction benefit because they can switch to a less harmful substance, but opponents argue that this could encourage abstainers to begin using the harm reduction method or even the original addictive good. This paper builds on theories of addiction to model the introduction of a harm reduction method, and it demonstrates the conditions under which each side is correct. The three key factors determining whether the introduction of a harm reduction method reduces or worsens health harms are: 1) the enjoyableness of the harm reduction method, 2) the addictiveness of the harm reduction method, and 3) the substitutability of the harm reduction method with the original addictive good. Knowledge of these conditions can help inform regulation of harm reduction methods.
For helpful comments, we thank Catarina Goulao, Catherine Maclean, Jesse Matheson, Michael Pesko, Luca Piccoli, Pedro Pita Barros, Holger Strulik, and participants in the following seminars and conferences: the University of Duisburg-Essen seminar, the Toulouse School of Economics seminar, the Essen Health Conference 2022, the EuHEA 2022 seminar, and the ASHEcon 2022 conference. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.