• Strongly associated with peer influence, family disruption, school neglect/disengagement, social vulnerabilities, gang association, perception of substance use as a means of gaining social popularity 
• Includes use and encouragement of use, parental separation, social media addiction (problematic use), anti-social peer groups 

Illicit substance abuse among Sri Lankan teenagers is strongly associated with peer influence (both use and the encouragement of use), family disruption (parental separation), school neglect and disengagement, social vulnerabilities such as social media addiction (problematic use), gang (anti-social peer groups) association, and the perception of substance use as a means of gaining social popularity. 

These findings were made in an original research on "Patterns and risk factors of illicit substance abuse by Sri Lankan teenagers: A case–control study" which was authored by K. Dayasiri (attached to the Kelaniya University's Medical Faculty), M. Samarasinghe and I. Gawarammana (attached to the same Faculty of the Peradeniya University), G. Gunarathna (attached to the Galle National Hospital, Karapitiya), and U. Sandakelum (attached to the Colombo North Teaching Hospital, Ragama), and published in the British Medical Journal's Paediatrics Open journal, in March of this year (2026).

Illicit substance abuse among adolescents is an emerging public health challenge in Sri Lanka. Understanding social, familial, peer and school-related determinants is essential to inform targeted prevention and intervention strategies. 

Illicit substance abuse among adolescents is a growing public health concern worldwide, with profound implications for physical health, mental well-being, educational attainment, and long-term social outcomes (an Indian study, and L. Degenhardt, E. Stockings, G. Patton, W.D. Hall and M. Lynskey's "The increasing global health priority of substance use in young people"). Adolescence represents a critical developmental period characterised by neurobiological vulnerability, heightened risk-taking behaviour, and increased sensitivity to peer influence, making teenagers particularly susceptible to substance use initiation and progression (C.J. Hammond, L.C. Mayes and M.N. Potenza's "Neurobiology of adolescent substance use and addictive behaviours: Treatment implications"). Multiple determinants of adolescent substance abuse include peer pressure, family dysfunction, and socio-economic adversity, but, the relative contribution of these factors varies considerably across socio-cultural contexts (A.M. Nawi, R. Ismail, F. Ibrahim, M.R. Hassan, M.R.A. Manaf, N. Amit, N. Ibrahim and N.S. Shafurdin's "Risk and protective factors of drug abuse among adolescents: A systematic review").

In South Asia, and particularly in Sri Lanka, adolescent substance abuse has emerged as an increasingly visible challenge for health, education and social protection systems (K. Dayasiri and R. Alagiyawanna's "Patterns of illicit substance use among children in the Western Province [WP] of Sri Lanka – A cross-sectional study"). Rapid urbanisation, widening social inequities, changing family structures, and increased exposure to digital media have altered adolescents’ social environments, potentially amplifying vulnerability to substance use (J. Liu, L. Charmaraman and D. Bickham's "Association between social media use and substance use among middle- and high school-aged youth"). 

Teenagers undergoing rehabilitation for substance abuse represent a particularly vulnerable group. These adolescents often experience overlapping adversities, including disrupted family relationships, peer networks that normalise substance use, exposure to violence or neglect, and unmet mental health needs (L.L. Passetti, M.D. Godley and Y. Kaminer's "Continuing care for adolescents in treatment for substance use disorders"). Understanding the constellation of factors associated with substance abuse in this population is essential to inform prevention strategies, early identification, and targeted interventions (K. Dayasiri and G. Gunarathna's "Mothering from the margins: Lived experiences of incarcerated substance-abusing mothers and the developmental risks faced by their children in Sri Lanka").

Methodology 

Study setting and population

Dayasiri et al.'s analytical, case–control study was conducted at one of the country’s principal tertiary referral centres for inpatient adolescent substance rehabilitation - the Youth Drug Addiction Prevention, Treatment and Rehabilitation Centre, Kandy. The study was carried out over an 18-month period from March 2024 to September of last year (2025). 

The study population was comprised of adolescents aged 10–17 years. Cases were defined as teenagers admitted for in-house rehabilitation for illicit substance abuse, diagnosed through clinical assessment by the treating multidisciplinary team, including consultant psychiatrists, in accordance with national clinical protocols. All eligible adolescents admitted during the study period were approached for recruitment. Controls were age-matched and sex-matched adolescents without a history of substance abuse who presented to the Outpatient Department of the North Colombo Teaching Hospital, for minor acute medical conditions. This Hospital primarily serves the WP. 

Inclusion criteria

Adolescents aged 10–17 years who were able to comprehend Sinhala or Tamil, were eligible for inclusion. Adolescents with severe cognitive impairment, acute medical or psychiatric instability were excluded from the study.

Study instrument and variables

Illicit substance abuse was defined as the current or recent use of one or more illegal psychoactive substances requiring inpatient rehabilitation, as determined by clinical assessment by the treating multidisciplinary team. 

Individual-level variables included age, sex, having a history of a diagnosed psychiatric disorder, academic difficulties, memory problems, extracurricular activity-related difficulties, social media addiction (self-reported excessive or uncontrolled use interfering with daily functioning), and perceptions of substance use as a means of gaining popularity. Familial variables included family structure (intact versus separated parents), parental substance use, parental involvement in substance dealing, household financial difficulties, exposure to domestic violence, the loss of a parent, and perceived parental neglect.

Peer-related variables comprised the peer use of illicit substances, peer encouragement to use substances, association with antisocial groups, experiences of bullying, dissatisfaction with friendships, and neighbourhood substance use. School-related variables included perceived school neglect, physical or emotional abuse at school, and school disengagement. Psychosocial variables included exposure to physical, emotional or sexual abuse at home or school, and self-harm-related thoughts and behaviours. 

Data collection

Among the cases, data collection was conducted after initial stabilisation during rehabilitation. 

Results 

Socio-demographic characteristics of the cases

A total of 108 teenagers with substance abuse were included as cases. The mean age was 15.8 years (standard deviation [SD] 2.4 years; range 10–17 years). Most participants resided in urban communities (69/63.8%). Nuclear family structures were reported by 72/66.7% of the cases.

A family history of substance abuse was reported by 34/31.5%. Single-parent households due to parental separation or death accounted for 21/19.4%. More than half of the adolescents reported witnessing domestic violence (56/52%).

The majority are Sinhalese (83/76.9%), followed by Muslims (17/15.7%) and Tamils (nine/8.3%). Participants were drawn from 15 Districts, with 47/43.5% residing in the Colombo District. Most families reported a monthly household income above Rs. 50,000 (85/78.5%). Family background characteristics of the adolescents with substance abuse are as follows: father (mean age was 39 years, age range 29-64 years, SD 6.1 years; 81.4% were educated below the General Certificate of Education Ordinary Level [O/L]; the common occupation was three-wheel driving; 26.9% abused substances; and 13.9% were substance dealers), mother (mean age - 34 years, age range 27-54 years, SD 4.2 years; 74.2% were educated below O/L; commonly, they were housewives and the common occupation was as a housemaid; only one abused substances; and only one was a substance dealer), and siblings (82/75.9% had siblings; 22% abused substances; and 7.4% were drug dealers).

Patterns of substance use by teenagers

Patterns of illicit substances used by the adolescents undergoing rehabilitation include heroin, cannabis/marijuana, cocaine, inhalants, smokeless tobacco, alcohol, electronic cigarettes, 3,4-Methylenedioxymethamphetamine/MDMA, amphetamines/crystal methamphetamine/Ice, hallucinogens, tranquilisers, and any prescription drugs.

All 108 cases had been introduced to substances by someone, most commonly by friends (92/85.2%), followed by siblings (three/2.8%), and parents, relatives and unknown sources (two each/1.9% each).

Reasons for initiating substance use

Self-reported reasons for commencing substance use among adolescents undergoing rehabilitation included experimentation, peer pressure, academic hardship, disrupted family, abuse, sexual stimulation, social media, bullying at school, to feel grown up, and boredom. These demonstrate the interplay of individual motivations, peer influence, emotional factors and environmental pressures contributing to initial substance use.

Factors sustaining continued substance use

The perceived drivers that contributed to the continuation of substance use following initiation included the wide availability, instant gratification, misinformation, isolation, to enhance performance, to be in control, rebellion, experimentation, curiosity, boredom, emotional trauma, societal pressure, family obligations, school stress, downtime, financial constraints, long-term medication, unsafe neighbourhood, mental illness, relationship break-up, easy accessibility, readily available pocket money, the appeal of popularity, and peer pressure. These factors span psychosocial, familial, educational and structural domains, reflecting the multi-factorial nature of ongoing substance abuse among teenagers.

A substantial proportion of participants reported prior self-harm-related thoughts and behaviours. Nearly half had previously thought of harming themselves (50/46.3%), while 24/21.5% reported previous thoughts of suicide. A smaller but concerning proportion had engaged in deliberate self-harm (16/14.2%), and five/4.4% reported a previous suicide attempt.

Analysis of risk factors

Potential risk factors associated with illicit substance abuse include individual-level risk factors (History of a diagnosed psychiatric disorder; Perception of substance use as a means of gaining social popularity; Problematic social media use; and Perceived lifetime neglect), family-related risk factors (Exposure to physical abuse within the home; Exposure to emotional abuse within the home; Exposure to sexual abuse within the home; Parental separation; Parental death; Perceived parental neglect; and Household financial hardship), school-related risk factors (Exposure to physical abuse at school; Exposure to emotional abuse at school; Exposure to sexual abuse at school; Perceived school neglect; and Experience of school-based bullying), and peer-related risk factors (Dissatisfaction with peer relationships; Peer use of illicit substances; Association with gangs or antisocial peer groups; Peer encouragement to use illicit substances; and Substance use among neighbours). Peer-related factors showed the strongest associations, including the peer use of illicit substances, the peer encouragement to use substances, and association with gangs. Family-related adversities such as parental separation and perceived parental neglect, as well as school neglect, were also significantly associated with substance abuse. Individual-level factors, including a history of psychiatric disorders, perceiving substance use as a means of gaining popularity, and social media addiction, demonstrated significant associations.

Independent risk factors for illicit substance abuse

Independent risk factors for illicit substance abuse among Sri Lankan teenagers include: the Perception of substance use as a means of gaining social popularity; Parental separation; the Peer use of illicit substances; Peer encouragement to use illicit substances; Problematic social media use; Association with gangs or antisocial peer groups; and Perceived school neglect. Peer-related exposures remained the strongest predictors after adjustment, including the peer use of illicit substances and peer encouragement to use substances.

Academic and functional difficulties associated with substance abuse

Cases were significantly more likely to report academic difficulties, memory problems and difficulties in extracurricular activities.

A high burden of psychological vulnerability was observed, with 46.3% reporting prior self-harm-related thoughts.

Discussion 

Multiple independent risk factors associated with illicit substance abuse among Sri Lankan teenagers were identified, underscoring the complex and multi-factorial nature of adolescent substance use. Even after adjustment for potential confounders, factors related to peer influence, family disruption, school neglect, social media addiction, and gang association remained significantly associated with substance abuse, highlighting critical domains for intervention.

Peer-related factors emerged as the strongest and most consistent predictors. Adolescents whose friends used illicit substances or actively encouraged substance use had markedly higher odds of substance abuse, reflecting the powerful role of peer norms and social modelling during adolescence. Peer networks not only facilitate access to substances but also normalise and reinforce continued use. The exceptionally high prevalence of peer substance use among cases suggests that prevention efforts must extend beyond individual-level education to address peer group dynamics and social environments (J.G. MacArthur, S. Harrison, M.D. Caldwell, M. Hickman and R. Campbell's "Peer-led interventions to prevent tobacco, alcohol and/or drug use among young people aged 11-21 years: A systematic review and meta-analysis", and K. Dayasiri, M. Samarasinghe and I. Gawarammana's "Curiosity, coercion and coping: Psychosocial drivers of youth drug use in Sri Lanka").

Perceiving substance use as a means of gaining popularity independently predicted substance abuse, pointing to the influence of social identity formation and perceived social rewards. This aligns with theories of adolescent behaviour that emphasise status-seeking and belonging as key motivators during this developmental stage (J.H. Pfeifer and E.T. Berkman's "The development of self and identity in adolescence: Neural evidence and implications for a value-based choice perspective on motivated behaviour"). The role of social media addiction as an independent risk factor further reinforces this notion, as online platforms may amplify exposure to substance-promoting content, distorted social norms and risky behaviours (O. Falade-Nwulia, M. Felsher, M. Kidorf, K. Tobin, C. Yang and C. Latkin's "The impact of social network dynamics on engagement in drug use reduction programs among men and women who use drugs").

Family-related factors also played a significant role. Adolescents from separated-parent households and those reporting parental or school neglect were at significantly increased risk. Family disruption may reduce supervision, emotional support and stability, thereby increasing vulnerability to maladaptive coping strategies such as substance use (a study in Asia-the Pacific Islands-Europe-America, and K. Guttmannova, M.L. Skinner, S. Oesterle, H.R. White, R.F. Catalano and J.D. Hawkins's "The interplay between marijuana-specific risk factors and marijuana use over the course of adolescence"). Similarly, perceived neglect by school reflects broader institutional disengagement, academic marginalisation, and reduced access to protective adult relationships, all of which may contribute to substance use initiation and its persistence (A.M.E. Zuckermann, W. Qian, K. Battista, Y. Jiang, M.d. Groh and S.T. Leatherdale's "Factors influencing the non-medical use of prescription opioids among youth: Results from the  Cohort study on Obesity, Marijuana use, Physical activity, Alcohol use, Smoking and Sedentary behaviour”, and an American study).

Association with gangs was another powerful independent risk factor, highlighting the intersection between substance abuse and broader antisocial or criminal networks. Gang involvement may facilitate access to substances, promote risk-taking behaviours, and entrench adolescents in environments where substance use is routine and instrumentalised for social cohesion or economic gain.

Notably, a substantial proportion of adolescents reported prior self-harm-related thoughts and behaviours, underscoring the close relationship between substance abuse and psychological distress (an American study). While causality cannot be inferred, this finding reinforces the need for integrated mental health assessment and support within adolescent substance rehabilitation services.

Taken together, these findings suggest that adolescent substance abuse in Sri Lanka is driven less by isolated individual pathology and more by interacting social, familial and structural factors. Effective prevention and intervention strategies must therefore be multi-sectoral, combining family-based interventions, peer-focused prevention, school engagement, digital literacy, and community-level approaches aimed at reducing gang involvement and substance availability.

Conclusion 

These findings highlight the need for comprehensive, multi-sectoral prevention and intervention strategies that extend beyond individual behaviour change. Strengthening family support systems, fostering positive peer and school environments, and addressing emerging digital and social risks are essential to reduce adolescent substance abuse and its long-term consequences. Prevention and intervention strategies should prioritise peer-focused approaches, family strengthening, school re-engagement, and integrated mental health support. Prevention strategies should prioritise peer-group- focused interventions and the early identification of high-risk social networks. Findings support integrated adolescent services combining substance abuse treatment, mental healthcare and school re-engagement.