Introduction: Substance use becomes censorious when it leads to harmful effects on individuals, their families, and the community. The nature of substance use in Sri Lankan context is poorly understood and empirical evidences are sparse. The study aimed to describe patterns of substance use and characteristics of the individuals enrolled in residential treatment at selected rehabilitation centers in Sri Lanka. Material and methods: A descriptive cross-sectional study was conducted among 205 individuals enrolled in selected rehabilitation centers. Pretested interviewer-administered questionnaire was used to collect data. Data were analyzed using descriptive statistics. Results: Most of the individuals who enrolled in residential treatment at selected rehabilitation centers were unmarried (n = 124, 60.5%), Sinhala (n = 186, 90.7%), Buddhist (n = 166, 81.0%), males (n = 202, 98.5%) and belonged to the young adult age (18-35 years) category (n = 178, 86.8%). All the participants were poly-drug users and cannabis was the most commonly used (n = 183, 89.3%) illicit drug followed by heroin (n = 172, 83.9%), methamphetamine (n = 150, 73.2%) and cocaine (n = 78, 38%). The most (n = 152, 74.1%) problematic substance for life was heroin. Most of the participants (n = 149, 72.7%) had used drugs several times per day. The mean duration of substance use was 7 ± 5 years. Participants (n = 177, 86.3%) reported that the substances were available in their residential areas and their friends (n = 197, 96.1%) were also using the substances. Conclusions: Pattern of substance use and characteristics of the individuals were unique in Sri Lanka and need to be considered when implementing and strengthening the programs for drug prevention and rehabilitation.

Purpose This study aims to evaluate the perceived effectiveness of residential treatment which follows the therapeutic community (TC) model for Sri Lankan individuals with substance use disorder (SUD). Design/methodology/approach A descriptive cross-sectional study was carried out in two selected residential treatment centers which follow the TC model as a rehabilitation approach. All the clients of the selected residential treatment centers were invited to take part in the study and data were collected from 75 consented male participants using an interviewer-administered questionnaire. The perceived effectiveness of the residential treatment was assessed using the Treatment Effectiveness Assessment instrument. Data were analyzed using descriptive statistics. Findings Most of the participants were Sinhalese (98.7%, n = 74) with a mean age of 27.0 ± 6.0 years. The average duration in which participants stayed at selected centers was 8.0 ± 4.0 months. Most of the participants reported that the encouragement during the program was sufficient (89.3%, n = 67), psychological support was satisfactory (89.3%, n = 67), freedom (69.5%, n = 52) and facilities were adequate (76.0%, n = 57) within the program. A higher proportion of participants said that the counselors and program guides were friendly (80.0%, n = 60), and participants were allowed to communicate with their family with restrictions (92.0%, n = 69). The mean perceived effectiveness score (score range 1–40) was 34.0 ± 7.0 and the four domain scores (score range 1–10) were substance use (9.0 ± 2.0), health (8.0 ± 2.0), lifestyle (9.0 ± 2.0) and community (9.0 ± 2.0). The majority (88.0%, n = 66) of the participants perceived a high level of treatment effectiveness. Originality/value There is a paucity of empirical evidence on effectiveness of TC model for individuals with SUD in South Asian countries including Sri Lanka. The findings of this study highlight that the participants perceived higher effectiveness of the residential treatment which follows the TC approach for Sri Lankan individuals with SUD.