Introduction

Young people's use of tobacco, alcohol, and other drugs causes concern. Early use of psychoactive substances can be harmful to health in the short term—for example, through injuries sustained or inflicted while intoxicated—and can lead to lasting patterns of consumption that increase the risk of many chronic diseases and social problems.1 2 Recent concern in the United Kingdom has focused on issues such as continued high levels of smoking by young women, binge drinking and associated antisocial behaviour by young people in general, and higher levels of cannabis use in adolescents than in most European countries.^w1

One potential approach to reducing the use of psychoactive substances in young people is to control their availability, but public policy in this area has tended to tackle tobacco, alcohol, or illicit drugs in isolation and is not necessarily based on evidence about what works.3 We review the research evidence on availability and answer two key questions. Firstly, how easy is it for young people in the UK to obtain tobacco, alcohol, and other drugs? Secondly, do measures to control availability affect young people's patterns of use? We concentrate on measures affecting price, tax, importation, licensing, sales practices, illicit markets, and enforcement in all of these areas. We do not deal with production, prohibition, rationing, marketing, or controls on possession or use (see bmj.com for rationale).

Sources of evidence

This article is based on evidence about availability synthesised from nine population surveys of people aged under 25 in various parts of the UK and on evidence synthesised from 30 reviews (including seven systematic reviews) of the effects of measures to control availability on patterns of use (specifically hazardous use by young people, where available) and health outcomes. Where review level evidence was insufficient, we included relevant primary research and data from official reports. A …