Psychosocial and Environmental Determinants of Psychoactive Substance Use Disorders Among Youth in Nigeria: A Systematic Review

Background Substance use among adolescents and young adults is a growing public health concern in Nigeria and other low- and middle-income countries. Despite increasing prevalence, there remains limited systematic evidence on the psychosocial and environmental predictors of substance use disorders in this population. Existing studies often focus on isolated substances or risk factors, overlooking the complex interplay of determinants across developmental stages. Methods This systematic review synthesized findings from 22 peer-reviewed studies published between 2015 and 2025 that examined substance use among adolescents and young adults in Nigeria. Databases searched included Web of Science, PubMed and African Journals Online. Studies were selected based on relevance to psychosocial, environmental, and developmental predictors of substance use. Data were extracted and analyzed thematically to identify recurring patterns and gaps. Results Findings revealed that adolescent substance use in Nigeria is shaped by emotional neglect, peer pressure, family dysfunction, socioeconomic hardship, and weak institutional support. Most studies (86.4%) used cross-sectional designs and focused on mixed substances (59.1%). Alcohol use ranged from 30.6% to 82.5%; tobacco from 5.5% to 35.3%. Early initiation, often before age 15, was common. Mental health outcomes appeared in 68.2% of studies, and several supported the self-medication hypothesis. Longitudinal and multi-level approaches were notably lacking. Conclusion The review highlights the urgent need for comprehensive, multi-factorial research on adolescent substance use in Nigeria. Future studies should adopt integrative models that account for developmental trajectories, psychosocial stressors, and environmental contexts. Strengthening regulatory frameworks and early intervention programs is essential to mitigate long-term health consequences and reduce the burden of substance use disorders in this vulnerable population.