does the theory-driven program affect the risky behavior of drug injecting users in a healthy city? a quasi-experimental study

background: the horror of hiv/aids as a non-curable, grueling disease is a destructive issue for every country. drug use, shared needles and unsafe sex are closely linked to the transmission of hiv/aids. modification or changing unhealthy behavior through educational programs can lead to hiv prevention. the aim of this study was to evaluate the efficiency of theory-based education intervention on hiv prevention transmission in drug addicts. methods: in this quasi-experimental study, 69 male drug injecting users were entered in to the theory-based educational intervention. data were collected using a questionnaire, before and 3 months after four sessions (group discussions, lecture, film displaying and role play) of educational intervention. results: the findings signified that the mean scores of constructs (self-efficacy, susceptibility, severity and benefit) significantly increased after the educational intervention, and the perceived barriers decreased (p< 0.001). also, the history of hiv testing was reported to be 9% before the intervention, while the rate increased to 88% after the intervention. conclusion: the present research offers a primary founding for planning and implementing a theory based educational program to prevent hiv/aids transmission in drug injecting addicts. this research revealed that health educational intervention improved preventive behaviors and the knowledge of hiv/aids participants.