Since the late 1980s, research has shown that drug abuse treatment is effective HIV prevention. Drug abusers in treatment stop or reduce their drug use and related risk behaviors, including risky injection practices and unsafe sex.²⁰ Drug treatment programs also serve an important role in providing current information on HIV/AIDS and related diseases, counseling and testing services, and referrals for medical and social services.

Combined pharmacological and behavioral treatments for drug abuse have a demonstrated impact on HIV risk behaviors and incidence of HIV infection.²⁰ For example, recent research showed that when behavioral therapies were combined with methadone treatment, approximately half of study participants who reported injection drug use at intake reported no such use at study exit, and over 90 percent of all participants reported no needle sharing at study exit.²¹ While these findings show great promise for achieving reductions in sexual and drug-related risk behaviors, studies are now needed to determine the longterm effectiveness of such interventions.

Moreover, drug treatment has also been shown to decrease cocaine use from an average of 10 days per month at baseline to 1 day per month at 6-month followup among noninjection cocaine abusers. Reduction in cocaine use was associated with an average 40 percent decrease in HIV risk across gender and ethnic groups, mainly as a result of fewer sexual partners and less unprotected sex.⁵ Among gay and bisexual men who abused methamphetamine, comprehensive behavioral treatment reduced sexual risk behaviors and sustained those reductions for at least 1 year following substance abuse treatment.²²

Behavioral treatments have also shown promise for enhancing adherence to antiretroviral therapy. Interventions aimed at increasing HIV treatment adherence are crucial to treatment success, but usually require dramatic lifestyle changes. Effective treatment often includes providing a consistent medical regimen to counter the often irregular lifestyle created by drug abuse and addiction.