Effect of the market withdrawal of carisoprodol on use of other prescribed drugs with abuse potential.

Carisoprodol, a centrally acting muscle relaxant indicated for acute lower back pain, has been available in Europe and the United States since 1959. Studies indicating increased risk of abuse or addiction led to withdrawal of the drug from the market in Norway and other EU countries in 2008. In this nationwide longitudinal prescription study of 53,116 individuals in Norway, previous users of carisoprodol switched, to a limited extent, to other prescribed drugs with abuse potential after the withdrawal.