Drug users are at risk of contracting HIV and hepatitis through sharing contaminated needles. A lot of countries run needle exchange programmes which allow drug users to bring in used needles and swap them for new, clean ones. This is usually done by coming in to see a mental-health professional who can often counsel people at the same time. However, in order to preserve drug users' anonymity and extend the hours of the service some countries have introduced syringe vending machines. A review of studies into the use of syringe vending machines has found that the machines increase access to sterile needles, reach drug addicts who might not otherwise use needle exchange services and help to reduce the unsafe disposal of needles.
Islam, M.M. and Conigrave, K. M. - Syringe vending machines as a form of needle syringe programme : advantages and disadvantages Journal of Substance Use June 2007, 12(3), 203-212