This multi-regional convenience sample provides an overview of substance use patterns among university students in Saudi Arabia, identifying prevalence estimates, substance-specific profiles, and key demographic, academic, and psychosocial correlates. The findings contribute to the growing body of evidence on substance use among young adults in the region and highlight several context-specific patterns that warrant attention from policymakers and university health services. However, these findings should be interpreted cautiously, as the use of lifetime measures does not capture current substance use patterns or severity of involvement. In addition, the convenience sampling approach and overrepresentation of students from medical and health sciences faculties may limit the generalizability of the findings to the broader university student population in Saudi Arabia.

Nearly half of the surveyed students reported lifetime use of at least one substance when tobacco was included, while the prevalence of non-tobacco substance use remained considerably lower. This distinction is critical in the Saudi context, where tobacco use is socially more tolerated and legally accessible compared with other psychoactive substances. Similar to prior studies from neighboring countries, tobacco emerged as the most prevalent substance, reinforcing its role as the dominant form of substance use among university students in conservative settings (16).

Smoking remains a major preventable public health issue with global impacts on morbidity and mortality. In Saudi Arabia, tobacco use is common, especially among adolescents and young adults. The prevalence observed in this study reflects lifetime tobacco use and is therefore not directly comparable to studies reporting current smoking prevalence. This study found a higher prevalence compared with the 11.65% at King Saud University and the 16.2% nationwide reported by Albuhairan et al., as well as the 20.7% in Jazan (17–19). These differences should be interpreted cautiously given variations in measurement approaches. Internationally, prevalence varies: 17.2% in Nairobi, 20.7% in India, and 22.5% in Egypt (20–22). In contrast, countries like Canada report very low rates, around 6.8% (23).

The relatively low prevalence of alcohol and illicit drug use observed in this study contrasts sharply with reports from Western and some African settings, where alcohol predominates among university students (6–8). This discrepancy is likely explained by legal restrictions, religious prohibitions, and cultural norms in Saudi Arabia, which limit availability and increase social and legal consequences of alcohol and illicit drug use (9). Additionally, underreporting may have occurred due to sociocultural stigma and legal sensitivity surrounding substance use. These contextual factors have consistently been shown to shape substance use profiles across regions, rather than eliminating substance use.

Notably, sedatives and sleeping pills constituted the most commonly reported non-tobacco substances. This pattern has been observed in other studies among health-related student populations in Saudi Arabia and may reflect a combination of academic stress, sleep disturbances, and relatively easier access to prescription medications (14). However, as the questionnaire did not distinguish between prescribed and non-prescribed use, these findings should be interpreted with caution and cannot be assumed to represent misuse. Sedative use in this context may reflect a heterogeneous pattern, including both medically prescribed use and potential non-medical use. Although non-tobacco substances, particularly sedatives, were examined in descriptive and bivariate analyses, multivariable modeling was not feasible due to sparse data and instability in regression estimates, and therefore these findings should be interpreted with caution. Notably, 7.1% of participants reported use of “other drugs,” which was higher than the reported use of some specific substances such as hallucinogens and amphetamine-type stimulants. This category likely represents a heterogeneous group of substances not explicitly captured by the survey instrument. In the Saudi context, this may include emerging or less commonly studied substances; however, the lack of specificity limits interpretation and highlights a measurement limitation of the instrument.

Marked gender-specific patterns were identified, with tobacco, hallucinogens, amphetamines, and alcohol use being more prevalent among males, while sedative use was more frequently reported by females. Importantly, users of non-tobacco substances were predominantly female (75%), representing one of the most striking findings in the study and highlighting distinct gender-specific patterns of substance use. These findings align with emerging regional evidence suggesting that gender differences in substance use are substance-specific rather than uniform. While males continue to dominate in socially visible and traditionally stigmatized substances, females may be more likely to engage in the use of prescription or medically framed substances, possibly as a coping strategy for stress, anxiety, or sleep problems (24, 25).

An inverse relationship between tobacco use and academic performance was observed, with tobacco-only users exhibiting the lowest proportion of high academic achievers (26, 27). This finding is consistent with prior research demonstrating that substance use can negatively affect concentration, motivation, attendance, and cognitive functioning. Conversely, students using non-tobacco substances, specifically sedative use, demonstrated higher GPAs, a finding that appears counterintuitive and diverges from much of the existing literature (28). The finding that tobacco-only users were older than other groups may reflect greater cumulative exposure over time, increased social independence, or longer duration of risk behaviors, all of which may contribute to higher likelihood of tobacco use among older students.

This paradoxical association may be explained by several factors. One possible explanation is that some high-achieving students may be more inclined to use certain substances, particularly sedatives or stimulants, as perceived tools for managing academic pressure, sleep deprivation, or performance demands (19, 29). Alternatively, this may reflect differential reporting bias or selective use of substances perceived as “functional” rather than recreational. However, given that the questionnaire did not distinguish between prescribed and non-prescribed use, and the cross-sectional design relies on lifetime measures, these findings should be interpreted with caution. Causal relationships cannot be established.

Consistent with prior studies, substance use was associated with higher self-reported rates of anxiety or depression, particularly among users of non-tobacco substances (30, 31). In the multivariable model, self-reported anxiety or depression was also significantly associated with higher odds of tobacco use, suggesting that psychological distress may play an important role in substance use behaviors. It is plausible that psychological distress contributes to the initiation or continuation of substance use, while substance use itself may exacerbate mental health symptoms, creating a bidirectional relationship (32).

Peer influence emerged as a critical determinant, with peer pressure showing a strong independent association with tobacco use (33). During model development, peer-related variables were carefully evaluated due to potential conceptual overlap. The variable “having friends who use substances” was excluded from the final multivariable model because it introduced instability in effect estimates and reduced interpretability. This likely reflects the fact that different peer-related measures may capture overlapping but distinct dimensions of social influence, such as direct behavioral pressure versus broader social exposure (34). Retaining peer pressure in the final model provided a more stable and theoretically consistent representation of peer influence. These findings highlight the importance of carefully distinguishing between different aspects of peer influence when examining social determinants of substance use.