Access to Substance Abuse Treatment Act of 2013

Access to Substance Abuse Treatment Act of 2013 - Amends the Public Health Service Act to authorize the Secretary of Health and Human Services (HHS) to make grants to: (1) increase the availability of treatment for abuse of heroin, cocaine, methamphetamine, 3,4-methylenedioxymethamphetamine (ecstasy), and phencyclidine (PCP); (2) provide vouchers to individuals in underserved populations for authorized services related to such treatment; and (3) establish programs to provide for and coordinate the provision of wrap-around services, such as medical services, job training services, and housing assistance, to individuals re-entering the community after successfully receiving treatment for abuse of such substances.

Revises the grant program to provide residential substance abuse treatment to pregnant and postpartum women to: (1) make caregiver parents eligible for such program, (2) make Indian tribes and tribal organizations eligible for grants, and (3) set forth the priority for allocation of grants.

Requires the Director of the National Institute on Drug Abuse to conduct research on the effectiveness of the use of agonist and antagonist drugs to reduce the problems associated with stimulant abuse, including cocaine and methamphetamine abuse.

Requires the Secretary to seek to enter into a contract with the Institute of Medicine to complete a literature review on the effectiveness of agonist and antagonist drugs for the treatment of stimulant abuse, including cocaine and methamphetamine abuse.

Requires the Comptroller General to study: (1) the impact of the programs authorized by this Act on the effectiveness and availability of treatment for abuse of heroin, cocaine, methamphetamine, 3,4-methylenedioxymethamphetamine, and phencyclidine; (2) how the level of federal funding available for such treatment compares to the amount necessary to provide adequate treatment; and (3) the impact of effective treatment on cost savings due to the reduced need for criminal justice and other services.

Declares that this Act shall not be construed to increase the amount of appropriations that are authorized to be approved for any fiscal year.