Prevalence of substance use and knowledge of its effects among secondary school students in Lagos, Nigeria.

Background: World Health Organization defines substance use as harmful or hazardous use of psychoactive substances, including alcohol and illicit drugs. There is an increased rate of substance use among youths and adolescents. Substance use significantly increases the risk for mental disorders.

Aim: The aim of this study was to determine the prevalence of substance use and knowledge of its effects among secondary school students in Lagos, Nigeria.

Setting: The study was conducted among Secondary schools in Lagos, Nigeria.

Methods: We conducted a cross-sectional, descriptive study among 800 participants who were selected using a multi-stage sampling method. The instrument for data collection was the amended WHO students' drug-use questionnaire. The data were analysed using Epi Info 7 software.

Results: The lifetime prevalence of substance use was 13.6%, while current users' prevalence was 6.9%. Apart from alcohol consumption, the substance most frequently used was tramadol (52.7%), followed by marijuana (36.4%). Almost all the participants (98.1%) were aware of substance use. Most students (88.7%) were able to identify the effects of substance use, including short-term complications (79.1%) and long-term complications (61.1%).

Conclusion: The high prevalence of alcohol and tramadol use among the participants underscores the need for stricter government policies on the accessibility of these products to adolescents and the need for increased awareness of their effects.

Contribution: The lower knowledge of long-term complications of substance use (61.1%) in comparison to short-term complications (79.1%) underscores the need for further research and increased advocacy on long-term complications of substance use among youths and adolescents.