Abstract
Background: Bullying and substance use are behaviours that occur among adolescents and have potentially adverse implications for normal development, health, and functioning in adulthood. This study aimed to determine the pattern of psychoactive substance use and its relationship with bullying among adolescents in Calabar, Nigeria.

Methods: In this cross-sectional study, 420 adolescents were randomly recruited from eight secondary schools in Calabar. After informed consent was obtained, a sociodemographic questionnaire, the Adolescent Peer Relations Instrument, and a screening tool for psychoactive substance use were administered. Data was analysed using SPSS version 22, and the alpha level was set at 0.05.

Results: Respondents were 201 (47.9%) males and 219 (52.1%) females, with a mean age of 13.98 (SD = 1.79). Prevalence of past-year use was 18.8% for alcohol, 12.4% for inhalants, 6% for stimulants, 6% for cocaine, and 3.3% for cannabis; use of tobacco, opioids, sedatives, and
hallucinogens was below 3%. Mean bullying and victimisation scores were 28.8 and 31.4, respectively. Drug users had significantly higher mean scores on both dimensions (p < 0.05). In regression analysis, illicit drug use independently predicted bullying (B = 6.71, 95% CI: 3.66–
9.77, p < 0.001) and victimisation (B = 5.84, 95% CI: 1.98–9.71, p = 0.003) scores, after adjusting for age, gender, and school type.

Conclusion: Bullying behaviour and psychoactive substance use are prevalent among adolescents in Calabar. Illicit drug use significantly increases the likelihood of both perpetrating and
experiencing bullying, highlighting the need for targeted, school-based mental health and
substance use interventions.

Key words: Bullying, Adolescent, Substance-Related Disorders, Psychoactive Drugs, Nigeria.