Naloxone, an injectable opiate antagonist, can immediately reverse an opiate overdose and prevent overdose death. We sought to determine injection drug users' (IDUs) attitudes about being prescribed take-home naloxone. During November 1999 to February 2000, we surveyed 82 street-recruited IDUs from the San Francisco Bay Area of California who had experienced one or more heroin overdose events. We used a questionnaire that included structured and open-ended questions. Most respondents (89%) had witnessed an overdose, and 90% reported initially attempting lay remedies in an effort to help companions survive. Only 51% reported soliciting emergency assistance (calling 911) for the last witnessed overdose, with most hesitating due to fear of police involvement. Of IDUs surveyed, 87% were strongly in favor of participating in an overdose management training program to receive take-home naloxone and training in resuscitation techniques. Nevertheless, respondents expressed a variety of concerning attitudes. If provided naloxone, 35% predicted that they might feel comfortable using greater amounts of heroin, 62% might be less inclined to call 911 for an overdose, 30% might leave an overdose victim after naloxone resuscitation, and 46% might not be able to dissuade the victim from using heroin again to alleviate withdrawal symptoms induced by naloxone. Prescribing take-home naloxone to IDUs with training in its use and in resuscitation techniques may represent a life-saving, peer-based adjunct to accessing emergency services. Nevertheless, strategies for overcoming potential risks associated with the use of take-home naloxone would need to be emphasized in an overdose management training program.