Substance abuse among adolescents poses a growing threat to public health and academic achievement, particularly within secondary schools’ students in Abuja Municipal Area Council (AMAC), Nigeria. This study investigates the prevalence, factors influencing, and consequences of substance abuse among senior secondary school students in AMAC, with a specific focus on its impact on academic performance. Using a cross-sectional design, data were collected from 361 students across ten (10) randomly selected public and private schools, supplemented by insights from parents, teachers, and school counselors. The results revealed a high prevalence of substance use (54%), with alcohol being the most commonly abused substance (45%). Most students obtained substances from peers, with many using them during school hours and struggling to discontinue usage. Although socio-demographic factors such as age, gender, and school type showed no statistically significant association with substance use, peer influence, perception ofsubstances as anxiety relief and exposure to substance-positive media and community environments were significantly linked to usage. Surprisingly, the correlation between substance abuse and academic performance, though trending toward lower achievement among users, was not statistically significant. Nonetheless, stakeholders perceived significant societal effects, including increased crime, psychological distress, and school dropout rates; although only one-third believed sufficient efforts were being made to address the issue. The study concludes that peer influence, social media, and community norms are major drivers of substance abuse, underscoring the need for collaborative, multi-sectoral interventions involving schools, parents, health authorities and media to mitigate the trend and safeguard youth development.