Introduction While precise data are limited, approximately 75% of prisoners in various Iranian prisons report using drugs while incarcerated. Previous research has primarily focused on the intersection of incarceration, injection drug use, and infectious diseases, with less attention paid to the subcultural forces and institutional practices that shape prisoners’ substance use. The guiding research question of this study is: How do prisoners experience and navigate drug use within Iranian prisons? Method Grounded theory was utilized to examine how drug use is reinforced and functions within the prison environment. Data were collected through semistructured interviews with 60 participants (38 men and 22 women), aged 15–65, most of whom had been incarcerated for drug-related offences. Participants were recruited through snowball, maximum variation, and theoretical sampling techniques across both governmental and non-governmental settings. Findings Five key categories emerged: coerced conformity, addiction as governance, access and supply, polydrug use pattern, and struggle for sobriety. Prisoners are coerced to conform to drug use to maintain their social status and avoid isolation, while prison authorities appeared to tolerate drug use as a means of managing institutional behavior. Methadone Maintenance Treatment functioned less as a pathway to recovery and more as a practical tool to stabilize inmates and reduce violence, often coexisting alongside widespread illicit drug availability. Finally, attempts to recovery were constrained by subcultural and structural barriers, with success limited to a small minority of participants. Conclusion The study reveals that incarceration itself perpetuates and intensifies substance use, functioning as a mechanism of survival, social integration, and institutional control. Findings indicate that therapeutic efforts of prisons in response to drug-related offences face significant subcultural, structural, and institutional barriers, underscoring the urgent need for more humane, effective, evidence-based approaches to drug use dependency that extend beyond the confines of correctional institutions.
Nahid Rahimipour Anaraki (Tue,) studied this question.