Health plans have implemented cost sharing and administrative controls to constrain escalating prescription expenditures. These policies may impact physicians' prescribing and patients' use of these medications. Important clinical advances in the pharmacological treatment of addiction highlight the need to examine how pharmacy benefits consider medications for substance dependence. The extent of restrictions influencing the availability of these medications to consumers is unknown. We use nationally representative survey data to examine the extent and stringency of private health plans' management of naltrexone and disulfiram for alcohol dependence, and buprenorphine for opiate dependence. Thirty-one percent of insurance products excluded buprenorphine from formularies, whereas 55% placed it on the highest cost-sharing tier. Generic naltrexone is the only substance dependence medication that is both rarely excluded from formularies and usually placed on a lower cost-sharing tier. These findings demonstrate that pharmacy benefits have an impact on access to medications for substance abuse.