This brief is the updated version of the 2020 HRI brief Making the Investment Case: Cost-effectiveness evidence for harm reduction. The updated version is based on a comprehensive review of economic evidence for harm reduction, and it includes new evidence, with a particular emphasis on studies published since 2020 and in low- and middle-income countries. There is some overlap between the two briefings with the strongest evidence featuring in both.

Understandably, some advocates are concerned that, if too much focus is put on cost-effectiveness, governments and donors may prioritise finances over the quality of services, posing a threat to human rights-based, community-centred harm reduction.

Here, the principle of ‘nothing about us without us’ is key. Communities must be at the centre of all decisions that relate to their health, including financial ones. Economic analyses should not be the only basis on which budget decisions are made. Equity, human rights and communities must be at the centre of financing for health and harm reduction or it will not be sustainable.

While the cost of providing OAT varies due to supply and service delivery factors, studies show similar costs per client per day for methadone across a number of settings, such as Nairobi, Kenya (US$1.49), Vietnam (US$1.01) and Indonesia (US$1.11).

In Malaysia, researchers showed that the national NSP was cost-effective and cost-saving. Even at lower coverage levels, NSP prevented 12,191 HIV infections, saving MYR 45.53 million (US$9.6 million) in treatment costs between 2006-2013

A study in Australia found that giving naloxone to people who are receiving OAT was cost-effective and is likely to save more than 650 lives between 2020 and 2030.

A study in Seattle, US estimated that establishing a DCR would save US$4.22 in associated healthcare costs for every dollar spent on operational costs.

Rsearchers in India found that integrated NSP, OAT and wider harm reduction support was cost-effective for HIV prevention, averting 996 HIV infections over three years.

In Belarus, an eight-month funding gap for harm reduction services reduced syringe distribution by 75% and reduced the impact and cost-effectiveness of the intervention. Without this funding gap, modelling suggests 53% more HIV infections would have been prevented.

The Ministry of Law and Human Rights in Indonesia spent around 42% of its total budget on managing prisons, including the food for people in prison. If Indonesia decriminalised personal possession of small amounts of drugs, the burden on prisons and other closed settings would be reduced by 40%.

The experience in Portugal shows both the effectiveness and cost-effectiveness of drug decriminalisation. Since personal possession of all drugs was decriminalised, the social costs of drug use, including the costs of drug-related deaths, criminal proceedings and incarceration, have fallen by more than 18%. This cost-saving is in addition to a decrease in drug-related deaths, HIV and HCV infections.